A. That would require the courts to be capable of having actual technical understanding which they absolutely do not if you look at the kind of rulings there have been for IT related stuff in the recent past.

B. Of course you can fake any kind of log in undetectable ways. Police has all sorts of deals with zero day software vendors these days. So even if it were so magically foolproof (which it isnt, nothing is) then you can never be sure.

C. Doesnt need to be "found" on a windows computer, they can just put it on a random USB drive and that would most likely hold up in court.