If you have any specific recommendation about the exact beach where to go or any specific resort any hint would be very welcome, either on the forum or in a private message
Malapascua is so small, the resort or hotel you book is pretty much at most a 10 minute walk from the dive shops. Just choose a dive shop on the south or west beaches, and get a resort on the same side. Regardless, its a small island so you shouldn't have troubles. And by small, I mean you can walk around the whole island in like 3 hours. And a heads up, there's not much else to do on that island except for dive and tanning, so I hope your wife brings a good book.
Cheers.