Yeah they're aware the new remixes suck and don't wanna sacrifice the first pop for it lol in some cases the returns were also last minute is probs why too
I mean yeah they're not good but that's not even it.
Look at AJ Styles debut. The music hit and everybody was like what the fuck is this shit? It wasn't until the 3/4 of the way through the intro to the song and the word Phenomenal popped up on the screen that the crowd reacted.
You use a known song because it's gonna make the people react right away. then you can debut a new song. It's actually smart on their part (if you need to change a song at all).