Dinos won't use "C" teritiary attack

[STuRoK]

This issue has plagued me recently. I cannot get my Therizino or other dinos to use the tertiary C attack. I remapped it long ago to MB4 and it worked fine until I came back to the game a month ago.
[Singleplayer Local]
I have tried remapping it back to C and other keys. My character does a punch when I press the key on foot, so it's not my mouse, etc.
I have unloaded all mods and it still doesn't work.
I have checked the game file integrity through Steam.
Edit: I played on a server and my Therizino still doesn't do it.

Does anyone have any insight? What else could it be, I'd rather not have to reinstall the whole game- that's a lot of data.
Thanks

[Chaser the Tiny Hippo]

What does it do when you press C or mb4?
You said that it makes you do a punch (primary attack) when you're on foot so maybe it's also mapped to the primary attack right now which is why it won't do the tertiary attack.

[STuRoK]

So I checked it more thoroughly by going into the Input.ini. It looks right. Also I had reset the keybinds and tested it.
ActionMappings=(ActionName="AltFire",Key=ThumbMouseButton,bShift=False,bCtrl=False,bAlt=False,bCmd=False)
ActionMappings=(ActionName="Fire",Key=LeftMouseButton,bShift=False,bCtrl=False,bAlt=False,bCmd=False)
ActionMappings=(ActionName="Targeting",Key=RightMouseButton,bShift=False,bCtrl=False,bAlt=False,bCmd=False)
I rechecked the action my character makes when I press MB4 and it does the pistol whip, and not the LMB action. Chainsaw does nothing for example with mb4.
This is really weird and has been really bugging me.

[Chaser the Tiny Hippo]

Wait, the mistake is thinking that AltFire is the tertiary attack. AltFire is the keybind name for melee.
The keybind for tertiary attacks is the same as your keybind for crouch. If you want mb4 to be your tertiary, set mb4 to crouch.

[STuRoK]

That doesn't make sense! but holy crap thank you so much!! that fixed it. I knew it was something dumb like that, well at least I hoped. way better than dealing corruption or conflict. haha it's laughable the relief I feel right now. Man, I appreciate you taking the time to help me!