check https://pinout.xyz, it has everything you need in term of mandatory connections.
Touch pHAT LEDs use the same driver chip as the cap touch buttons, over I2C, so if the buttons work but not the LEDs, that is rather surprising.
Ultimately it could be a power issue, with so many devices hooked up it’s hard to tell whether you could correctly operate all at the same time… in principle yes (I think, I haven’t checked for specific potential pin conflicts), but the reality might be different.
I’m guessing you’ll be missing the required power or ground connection for the LEDs to source/sink properly then! In fact, looking over the production files it’s a 5V connection you’ll be missing. We’ll get that documented on Pinout :D