@Squeaky Belle
In The End the Dazzlings and Trixie and the Illusions were disqualified.

@Background is Best Pony
 
Lol no problem. I’m pretty sure that’s what they were called. Not sure about the Muffins one. It definitely had “muffins” in the name though.

@Squeaky Belle  
YEET  
THEYre CANON  
MY CHILDREN ARE CANOn  
not really but I can be happy they used “The Planeteers” anyways.

I watched the Rainbow Rocks Musical last week. It had all the band names on the screen. Unfortunately my memory is horrible…but I can confirm that the top right and the one below it are Photo Finish’s band and the Diamond Dogs respectively.
 
Also yes that green environmentalist band is called “The Planeteers”.

@Background Pony #3DB9  
B1 was probably Diamond Tiara and Silver Spoon

@ColdGoldLazarus  
For Golden Hazel and the Dramas, I noticed Golden Hazel sitting with Indigo Wreath and Drama Letter after Flash stomped off. And since most of the Bands are trios, I’d say they were her bandmates.  
As for the ??? I think it might be the Wonderbolts? Soarin, Spitfire, and Fleetfoot were in the comics.

…HOW DID THE CUTIE MARK CRUSADERS NOT WIN THIS?!
 
…No, seriously, I wanted them to win as a big swerve in the movie. ;_;

Am I the only one who wants the humanized Diamond Dogs to have a David Bowie tribute band?
 
@bingo77  
And the Dazzlings? Or is that a case of “villains are supposed to do things like that”?

Eh, Rainbooms actually isn’t as bad as it seems at first, since its plural (as in the mane six are all Rainbooms, not dash specifically).
 
Plus the whole rainbow things being pushed lately has dash being completely unrelated to them, so its less about Dash and more about dash’s name being similiar in concept.

@bingo77  
What about “The Rainbooms” and “The Dazzlings”?
 
…Okay, that first one actually is an ego thing.

I actually kind of find “flash drive” kind of funny. Albeit its pretty egotistical for flash to name his band after himself though.

@Background Pony #8770  
Aw, crap, Forgot I was logged out.

So here’s what we have so far.
 
Left, top to bottom:  
The Diamond Dogs (?) [3]  
Trixie & The Illusions [3]  
Lyra & Bon Bon [2]  
??? [?]  
Snips & Snails [2]  
Bulk Biceps [1]  
The Rainbooms [5-7]  
Octavia [1]
 
Right, top to bottom  
The Snapshots (?) [3]  
??? [?]  
Golden Hazel & The Dramas (?)[?]  
The Dazzlings [3]  
The Planeteers [3?]  
Flash Drive [3]  
The Muffins [3]  
The Crusaders [3]
 
So I’d have to watch the movie again to try to get a better look at the two mystery emblems, but it might also help to look through various scenes to try to pick out who might comprise the other groups.
 
 
@Background Pony #F007  
Did this happen? I don’t recall.

@Masem  
There is no way anyone was worse than Snips and Snails.

@Masem  
Or they purposely let them in so that they could be utterly destroyed in the first round since music in this movie seems to do physical damage.
 

 
Which is why Bulk Biceps is my hero.

@Background Pony #1925  
@Shin32  
Also keep in mind there were qualifying rounds, so they could have failed then (That, of course, means they were WORSE than Snips and Snails…)

@Shin32  
We saw them painting a poster at the time of the music showcase. And if the painfully bad Snips and Snails got in, I doubt they failed the selection round.

Golden Hazel and the Dramas went against the Dazzlings. Her cutie mark is right there.

@Background Pony #1925  
Were they? I don’t remember seeing them anymore after the Battle of the Bands song. I don’t think they participated.

Which is Diamond TIara’s and Silver Spoon’s band? We know they were participating.

My bracket was shot to hell after Normal Normal’s duet with Raindrops upset Sapphire Shores.

I’m suspecting , from what I remember of the top left, that that’s the Diamond Dog group - the logo is rather crude comepared to the rest.

@Background Pony #3DB9  
There’s also the nerd contingent to consider.

@Roy-of-Asturia  
We saw the Diamond Dogs among the other bands during a crowd scene. So I guess they participated, too. The A2 group that lost against Lyra-Drop were probably Athletes and the ones that lost against the Dazzling Dramas.

From the top left:  
A1. ??? v Trixie & The Illusions (Rock)  
A2. Lyra-Drops (Grand Piano) v ???  
A3. Snips & Snails (Gangsta Rap) v Bulk Biceps (Violin, single entry)  
A4. The Rainbooms (Rock) v Octavia (Cello, single entry)
 
From the top right:  
B1. The Snapshots v ???  
B2. ??? v The Dazzlings (Vocals)  
B3. The Planeteers (70’s Rock) v Flash Drive (Grunge)  
B4. The Muffins (Novelty) v The Crusaders
 
 
And the tournament winners will receive A+’s on all subjects.
 
Please help me out. I think The Dazzling trio must have retired the Drama Club, or some other name.