Not an expert, but I find it fun to help with these and I have some related experience looking at Neo Geo MVS games.
21-23 are definitely your most suspect ones:
- 3 different chip brands (Hitachi, STMicroelectronics, Mitsubishi)
- Windowed EPROMs
-
Date Codes - Tough to see them all, but to me it looks like the 26th week of 2001 for chip 23, maybe 9th week of 2001 for chip 21 if it's YYWW format, and maybe 40th week of 2002 for chip 22?
All those signs point to them being added much later. Now, were they for a repair? Was it a factory repair or an amateur one? Does this distinction matter to you? All questions worth asking that I can't answer.
Considering the number of seemingly original chips (is S92 a catalog number for Hyper Fighting? MVS games do this, with game number - dash - chip location on all the silkscreens), I don't see how the board could be labeled an outright bootleg, but people have plenty of personal lines between "authentic" and not.