Green’s Dictionary of Slang

(US) to crush, to humiliate, quasi-euph. of fucked adj.¹

2015		(ref. to 2008) D. Trump on CNN Politics 23 Dec. 🌐 Once again, #MSM is dishonest. "Schlonged" is not vulgar. When I said Hillary [Clinton] got ‘schlonged’ that meant beaten badly.
2020		Vanity Fair Nov. 🌐 If the polls are correct, the president is about to get schlonged, bigly.