I don't know the origin of the name Misha but it sounds like it's closer to a Chechnyan Muslim name than an Arab one.
Gorbachev’s nick was Misha. An arab AQ guy would probably pick an alias to sound at least somewhat native to where he was recruiting and training, I suppose...
And the ‘on an unrelated’ thing. If you’re a jihad trainer, every case you’re involved in is related, no?
I guess they’re waiting for other shoes to drop before they
reveal who Misha is.