Permission? They are not Microsoft and I am not Apple it's just a free mod! I added list of mods which where i found meshes in, but only for information. I honestly write that i used models from another mods. Thats enough.
Afaik, 1257ad mod dev's for example would not really like if their work is used in some other mod without their permission. Warband modders are not Microsoft, no, but their work is still theirs and there's a certain rulebook regarding the models and textures created, some of them are OSP (free to use by anyone), some of them are not unless you contact the devs .You won't be sued or anything, it's more about being polite and respecting other people's right to do as they please with their creations. It's been like that for ages on the TaleWorlds forums.