"Asset use permission" straight does not apply to mods that have no NIFs or textures, FYI. ESP / ESL plugins are not "assets".
Interesting. Is that from the nexus rules or is it the result of some Creation Kit EULA? I'd love to have a source for that.
Where are you getting "just ask" from, also? That's not a thing in the default permission types at all.
"Just ask" is my simplification of the permissions. It was meant for mods that require you to get permission for asset use, modification use, or something related due to author notes.
I assumed that the merge might modify the files in some way and that mod authors saying you need permissions to use their assets actually included assets in the mod.