I wonder if them yelling "This is MAGA country motherfucker!" was part of the original script 
It definitely was, that's why he arranged to be on the phone with his manager at the time, so he'd have a witness because the street camera probably doesn't pick up sound
Honestly the reason he probably didn't give his phone to police was because he recorded the audio too in case he needed it to materialize miraculously later
"Why is there this wav file that perfectly recorded the whole attack"
"Oh you know I been fighting with the manager recently, needed some back up evidence in case I ended up in a he-said-she-said scenario y'know"