But adding microphones, doesn't make the video more believable, that's what doesn't make sense, if the microphones hadn't have been there nobody would have questioned it

I think the microphones are part of the original video (coz they only look out of place once biden blends in badly) but also I agree they don't blend in perfectly either after rewatching

At first I thought biden and the mics were recorded at the same time on the green screen, but then his hand wouldn't have gone in front of the mics if that had been done.

It's the added in mics that doesn't make sense because they don't need to be there to make the video believable, and biden is definitely added as well