1. "Trial by combat" means one person fights one other person, and the victor is considered "right."

2. And note the context! In this case it is clear that he is speaking of a one-on-one challenge where reputation is at stake, not life or limb, and where the combat is making the evidence public. Watch the video. Don't take my word for it: https://twitter.com/atrupar/status/1346847382768676864

I'm no Rudy fan, and I'm not going to try to justify what Trump and other Republicans have been doing, but give me a break. If Cranley isn't inciting, then neither was Rudy.