It may be passing aftertouch but not for the correct notes,
I had a similar situation where I thought the aftertouch wasn't being passed from keyboard through the mpc and out to the module but I could see the midi status light come on when I used aftertouch,
so I recorded 1 note c3 with the pads with varying aftertouch, all fine module reacted to it as it should, checked list edit and there was the note c3 followed by lots of entries of c3 aftertouch.
Then I tried the same thing using external keys, module didn't react, so looked at the list edit and there was the entry for note c3 but was then followed lots of entries for aftertouch c0
I then checked the keys straight to the module, that was fine so it wasn't the keys putting out the c0 aftertouch message.
This may be the mpc's way of converting / aggregating poly aftertouch into channel pressure ie mono aftertouch where any aftertouch on any keys effects all, which is fair enough if the mpc recorded the pads the same but it doesn't.
So if you want to use a keyboard to play your modules through the mpc check if they have poly aftertouch, if they do then you may be attached to another object by an inclined plane, wrapped helically around an axis
If there's no reason for your words, then your silence ain't absurd.