Carpenter bee and velvet ant

Carpenter bee found on the sidewalk. At first I thought it was hurt but by the time I got back from the walk it was gone. So maybe it just hit its head??

This was a really fast, didn’t want to stop for anything bug. Hard to get the shot.  I think it is of the Velvet Ants family Mutillidae  Velvet Ants (Mutillidae)