No good will come from Barr testifying before the house.
Let them whine and complain. If they are going to impeach they will do it regardless of Barr testimony. We already saw a preview of their actions during the Senate testimony.
They will use any Barr statements before the house to tarnish the President and add fuel to their fire.
They are the enemy treat them as such.
Barr should walk in and say........After two years, 19 lawyers, 40 FBI agents and 30 million dollars, they could find anything to pin on Trump or his people. Now leave me alone. Goodbye.