I think it's interesting that only 5 Republican senators voted to block Sen. Paul's motion to vote on the the constitutionality of the trial altogether, but I don't know that I agree that it means the conviction is "dead on arrival". What I really think it means is Republicans would rather not have the conversation about whether their rhetoric is encouraging violence, because it comes a little too close to home.
It's altogether possible that as additional information becomes available, we'll understand just how close to home that actually is, and additional GOP senators will feel shamed enough to actually decide this is bad and Trump should get his measure of blame. It is also altogether possible they will feel no shame whatsoever because they are totally lost, amoral, bloody-minded assholes. But what we are not going to do is avoid the conversation, however desperately Republicans might like to.