Minecraft Version 1.16.4
Forge Version 35.1.28
Modlist:

When Treemendous is enabled and I select the default world type, Yung's structures do not generate. Caves generate as they would in vanilla. The problem disappears upon deactivating the mod. I really like this mod's premise, but Yung's mods are ones that I cannot go without.

Is there a compatibility patch that I've missed, and if not, does the author intend to add compatibility?

I have all three of these installed in forge 35.1.0, and they seem to work together just fine. Have you checked the other mods you're using?

My own modlist, for reference: