And if he doesn't like how it turns out it will really reduce the value of the Vintera if he decides to sell it and there goes that $350 that he was hoping to pocket if he went down that road selling the Vintera.Keeping the Vintera is the right decision. I generally don't like Pau Ferro fretboards, but yours doesn't look that bad. However, if the looks of it really bother you (it does look a little weird with the LPB body), there's an easy fix. Get some Fiebings Leather Dye (either dark brown or black) and dye it. I've used the black dye on a Laurel fretboard and it turned out great. Looks like ebony and hasn't worn off after a year. Never tried it with Pau Ferro.
If what you really want is a maple fretboard neck, you could look for a maple Vintera neck and sell the Pau Ferro one. I put a Vintera 50s neck (7.25" radius vs the 9.5" on the Vintera 60s Modified neck) on an American Special and love it. There are several Vintera 60s roasted maple fretboard necks on Reverb right now. They're going for around $350.