This seems silly, the issue at hand is that there are really four facts that are relevant or possibly relevant that we know about this person and it's down to how you analyze each fact.
He's a young white dude
He donated to a progressive thing
He registered as a republican
He shot at Trump.
Each of you have to explain away some facts to make your theory work.
Ryuu: He's a generic shooter.
Shot at Trump but that's politically neutral, don't know why he donated to a progressive cause, but he's a registered republican so those two pretty much cancel one another out. Young white male was not included in the analysis, but I imagine a young white male is not a bastion of progressiveness on average.
Jimbo: He's a radical progressive terrorist.
Shot at Trump seems to be the most important fact to you and is difficult to square with anything other than democratic leaning. Registered as republican but that can be explained away and again is cancelled out by his donation to a progressive cause. Lastly his demographics make him likely to be progressive but that's up for debate.
In the end the same facts are there, and you're both just guessing at the other parts. The main contention is whether or not the target indicates political leaning. Under Ryuu's hypothesis it doesn't have to, under Jimbo's it is best explained with him disagreeing with Trump and most people that disagree with Trump are progressive so that's the best guess.
They're both just guesses and the only issue I see is that Jimbo wants to talk about how his thing is based on only facts and Ryuu's is opinions. They're both opinions based on the same set of facts and explaining them in different ways.
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