I have an idea, why don't they ask beerus to handle that goat????

That's the same thing they could have done with Zamasu.

They did ask Beerus to help with zamasu, and he did help. He destroyed the one in their timeline to prevent what happened in trunks time line to happen in theirs. The reason he didnt go to trunks timeline to help was because he couldn't. God of destructions aren't allowed to travel time and doing it is a grave offence that could end up in zeno destroying them.