Go to ...steamapps\workshop\content\570\855965029

ability_item_usage_[hero_name] is where the bots choose skills and talents, make sure the ability number corresponds to the skill.

For example, ability_item_usage_brewmaster have this:
Abilities[4] used to be Primal Split but since 7.32 it's now Primal Companion. Abilities[5] should be used instead. So it should look like this:
Make sure to scroll down and check Ability Usage Thinking, in the same example on line 425:
This checks for Primal Companion instead, just replace the right skill number and the bots will skill and use ulti again (bots still can be stupid though, Brewmaster in this example sometimes will buyback and use ulti while in fountain because teamfight is still going on).

After you edited the files change it to read-only so the file won't revert back. Doing this will also mess up the update if the scripts are updated, so remember to untick read-only before update. This does not work for online co-op.