If the voices were so similar then why not use original recordings? They were lip syncing to their own tracks anyway, what's the big deal? It just would have made it more authentic to me. Like in Selena, it wasn't Jennifer Lopez singing it was all Selena recordings, which is what the family wanted.
At the end of the movie the played one and Reese didn't sound so much like June imo.
Sony would have to have been paid a king's ransom for licensing the tracks, adding thousands, maybe millions of dollars to the budget. And they would have been lip syncing to someone else's tracks, which seems even less real, to me. Johnny and June weren't on screen, which is why I make that subjective distinction.
I don't think J. Lo can carry a tune in a bucket with wheels, so any attempt to re-record would have been a disaster and not an option. At the time, both J. Lo and Selena were only minorly known, which worked for the film. Gregory Nava made a moving portrait of Selena's life, so much so that I have to turn her music off when I hear it; it is far too upsetting.
Dan/NS