Several things come into play.
1st is that just because someone on the Net stated something, that doesn't mean they were accurate.
Secondly, just b/c a song is a bluesy tune, it doesn't mean all the 3rds will be flatted, particularly for the V chord----yes, even in a minor key.
Sometimes a 3rd (or any note) may be bent or slid into/out of or other variations may occur.
It's also not uncommon for a tune to be notated in a key that winds up requiring some notes to be adjusted w/an accidental every time they occur.
PPl take all sorts of approaches to notating music that may not be consistent.
Lastly, you may be absolutely correct abt yer initial question.
We can't hear the track but you can.
Does the backing track seem to have all minor chords in the relevant places ?
... most of you guys know way more about this than I ever will, your help is greatly appreciated.
You know enough abt keys, etc, to be able to lay out the quandary & why you wonder so give yerself more credit than you did in the OP, esp in regard to yer future knowledge !