Gladiator Begins (ULUS-10528)

[LunaMoo]

You can always get older builds on android from buildbot, however as far as I checked just now, the cheats are still all working in latest ppsspp.

The only problem I found was related to 60fps cheat which I just updated in the edit above, but it only affected refining cheat as far as I can tell. If you never used it and those cheats just don't work for you then I would guess you're trying to use it in different game version and I can't really help with that.
Through I would say this game is pretty fair without cheats, if you can't handle your opponent just try different moves/skills, all opponents have weaknesses and finding those is huge part of the fun.