Sorry for the really late reply. I also didn't know why they were banned, so I looked it up and here is the reasoning from a GDQ organizer:
"Phone emulators use various speed hacks, frame skipping, etc. PC emulators don't really do that anymore, it's not needed. But when your inaccurate smartphone emulator doesn't have any in-game lag due to all the (sometimes intentional) inaccuracies, it gives them a big benefit.
Star Fox is a great example. An accurate emulator will keep the slow, laggy frame rate of the original console. An inaccurate one will play much faster."
Basically, smartphone emulators are less accurate and use various hacks, both of which would give an advantage to players on these devices.
I'm not sure why it got deleted. Thanks for letting me know about this, I just re-submitted the run. Also, congrats on your recent WR.