few thoughts that may or may not work:

for that asopao or others that rely on medium-sized animal chunks in a sauce, you could try king oyster mushrooms, which i think are by far the best meat replacement and just so damn good generally. Chopped into decent-sized pieces and scored (important - really helps them soak up flavour) before a bit of frying, they give a really satisfying texture. Well-marinated firm/hard tofu can also help satisfy that craving for chunks of more chewy stuff, although could of course be a harder sell cos of the bad rap tofu gets with omnis. and for the small pieces of ham in that, i think a good replacement for small bits of ham etc in things like fried rice and soups is enoki mushrooms, which i think hit that satisfying texture and flavour note

for the papas rellenas or others that rely on mince, perhaps well-seasoned brown lentils or textured vegetable protein, with the seasoning including some smoked paprika to give more of the mince vibe? they can be bland and a bit weird if not seasoned well but it seems like the spices are doing the heavy lifting here anyway even when theres animal involved

of course you could always try the actual fake meats that people make, but im personally not so into those so i dont really have suggestions, and i kinda think they invite comparison with actual meat and might just really remind him that hes "missing out"

i have zero suggestions for the sweet stuff, sorry!