|So, before getting into this, I have to get this out of the way first. That was one hilarious music video! I also apologize for not being online to see your request! That out of the way, let's get into things.
Readability - I'm able to read your sentences without issue and basically follow along with where the story is going in this piece. That said, I do feel it's a little spastic as far as pacing is concerned. I was left mostly confused after reading your piece. It wasn't until I watched the music video that the missing context was added in. I think this may be, in part, a side-effect of taking the music video's story-boarding as a base and trying to stick with it. Music videos as a medium don't really have a solid story line these days and instead aim to illustrate whatever moral or point the artist was going for. They have the liberty of visual and audio cues to contextualize the words. As for how I'd fix this, I'd take the events as depicted in the music video and use them more as landmarks instead of going from one to the next. This would allow me to flesh out the different scenes (I.e. the restaurant sequences as well as the 'morning after' scenes). I feel this would allow us as authors the spacing required to add the missing context that we lose by adapting this from a music video to a piece of literary work. I'll give you half a star here since your piece mostly does the job. I just think it could do it better.
Composition - So, first off, I don't think Mr. Poe's quote really works for this piece. The poem "Dream within a Dream" was about how the internal mind was no different than the external one. In the poem this is illustrated by the sandy shore with crashing waves in the second stanza being tied together with his lover passing away before him in the external world. The fact the dreams in your piece are shown to be fake, I feel anyway, clashes with the sentiment of the quote. This isn't something I'm holding against you, mind you. Edgar's poem is wide open for interpretation, just a personal nit pick. The first part of your piece I want to discuss is the following line: "Yes! I would love -" she began, but couldn't finish because a piece of food lodged in her throat. "I would-" She coughed and collapsed from the lack of oxygen. On my first time through I didn't think this was something significant. It wasn't until I saw the scene play out in the video that is was significant in that the words were false. Or maybe in your telling of the story the words aren't false and she's just nervous? It's also possible that, just as I thought before, this isn't a significant event since she ends up marrying 'Real Quincy' anyway. I think a lot of this confusion would be fixed if this line was preceded by another sentence describing Kaily's mental state. How did she react to the ring? Did she like it? Did she not? Again, this is something the music video is able to take for granted thanks to audio and video as a medium, but we can only use words to paint what we mean.
The second line I'm going to pick at is "Duke may not have money, but he has what money can't buy," said Kailey. Duke removed her straitjacket and the two made out. What is it that Duke has that money can't buy? I'm assuming it's kindness because of how these sorts of pauper and prince stories go... but Duke never really gets a chance to display any kindness other than a caress on the cheek while she's trapped in a straitjacket. Furthermore, I feel Quincy (dream Quincy, not real Quincy) hasn't really been show to be unkind. She's been dating him long enough to get to a marriage proposal. He lets her live in his massive mansion, and the only time he really gets upset is when A) She burns down his mansion, and B) When she starts making out with another man. Both are things I feel he would be justified in being mad at her for. Again, I realize this is based on a music video, but this is another instance of words from the video lacking the context clues that gives the audience a better idea of what's going on. In the previous restaurant sequences, I'd give Duke a bit more positive characteristics and Dream Quincy some more negative characteristics in order to draw a better contrast between the two and thus make this line have more impact than it does. I'll touch on this a bit more in Story Flow, but as for composition, I'll give you a star overall, since the rest of the sentences didn't cause confusion upon reading them.
Story Flow - Being honest here, I think the story reads like you're starting out with one story, but on the ending you've glued in a different story's ending using the same characters. You have this back and forth between Billionaire Quincy and BusBoy Duke, but when the dream sequence is over we find that not only is Quincy not billionaire (Or someone of moderate financial standing) there's also not busboy to speak of. Comparing it to the dream sequence of this event at the beginning, I'm lead as a reader to conclude Kailey was expecting this proposal for some time now and has been nervous about it, hence the first dream. That has the problem of where the rest of the story fits in with the ending. Is there someone else named Duke she's interested in? Is she afraid of commitment and the busboy in her dreams is a manifestation of that? Or worse yet, has she already cheated on Quincy and the dream about burning down the mansion was some sort of allegory for what she thought would happen if he found out? There's no real way to tell because the details required to make the assessment aren't in the story. Sadly, I don't feel I can five you a star for Story flow due to all of the confusion that arises by plugging these pieces together without surrounding context to guide the reader one way or another.
Grammar - I didn't catch any overt grammatical errors, so you get a star in this category.
Enjoyment - While I believe your story-line here has some clean-up that needs to be done, I did enjoy reading it nonetheless. It was short and sweet, and I believe a general audience would be able to read this, get something out of it, and then move about thier day. Another star for you.
In summary, I feel a lot, if not all, of the issues I highlighted can be fixed by adding the context you lost when moving from a music video to the written word. It's important to illustrate the mental state of the character(s) we are following alongside and it is also important to ask yourself on a re-read, does this actually make sense? What are my readers going to get from this? Things like that. All in all, an enjoyable piece. Have a good day!