Based on the story there's a good chance it'll be one of these recordings: https://relisten.net/grateful-dead
Probably not because GD is not electric music. Also, there is/was a big taper scene there. This sounds like there was no recording going on.
I don’t think the Grateful Dead would be referred to as a “live electronic dance band.”
Assuming it’s a band most have heard of I was leaning toward Daft Punk, but maybe the Prodigy?