I have the formal training. Yes, the House can do it. Private individuals can’t get a writ to do it but the House or Senate can, they have standing and if granted it basically says do your danged job and enforce the law. Of course, Garland would use the BS defense of executive privilege, however executive privilege only applies if the executive was doing official job duties, and being interviewed by a special prosecutor is not an official job duty of the POTUS. Thus, No executive privilege applies. I have litigated executive privilege before at a highest state level. Governor did not want to be deposed in a case of reverse state contracting bid-rigging. Judge said no executive privilege applies, illegally interfering in state procurement matters is not an official job duty of a State governor.
So you are saying that Congress can issue a writ of mandamus, or that they can seek a writ from the courts?
If it is the former, than I stand corrected. If you are saying the latter, then that was what I suspected had to transpire.
As for the remainder of your comments, yes the fight only escalates from there.
My very initial comment was that the ground work was laid by securing the contempt of Congress charge, and that justice depends upon Trump winning, coupled with the Republican obtaining large majorities in both Houses of Congress to ensure impeachment first. Then, I had left this off, charges being brought by a Trump DoJ.