If the person who bought it for 38K is going to settle for the 115 and there are no other problems with the boat, it is not a bad deal at all. Of course you could flank that 115 with two 80's and make it a tripple, sell the kicker....Just kidding.
The 115 and 75 EFI are the same block and same weight (400 lbs). The HP is not really an issue (Maybe for insurance), but that HP is only achieved at high RPM, and should not stress the transom. Twin 90's have been put on these boats and they do fine. There are these 115 EFI's for less than 10 K on the internet. Rigging may be as much as $2,000, so for 50K you could have a very nicely outfitted boat with max hp...not a bad deal--if the rest of the boat is OK.
It will be interesting to see if the new owner finds his way to the C Brats, or is a C Brat, and what is performance numbers are.