I don't think there would be a structural issue as long as you left the original insert in place. You could probably find or make a small cap/plug to hide the insert, and maybe paint it.Asking for a friend (!):
Does any simply leave the original bolts in the holes on 3-point bridge conversions to 2-point and not bother filling the holes? Is it not poss to simply wind them in snug and leave them or is there a structural issue with the new holes being so close? On this one (love the colour!) it looks like the new bridge was actually installed a little bit more rearward than need be what with the intonation positions of the saddles, so the new holes could be a little bit further away from the original ones - I'm just thinking, sorry, my friend is just thinking ( ;-) ) that could be a lovely, lazy route to take?
I'd try it on my Epi E1, but the 2 piece bridge would cost more than I paid for the bass!
A plug like that would be another project for an industrious person with a 3D printer...
Please put Frank on. We need to talk!