If Trump has a problem with RINO's, who may be "pushing DeSantis" as you say, shouldn't he come out and say that's what his problem is?
Yes. Perhaps he doesn't want to go there yet. It would only help Trump and hurt DeSantis if he was more clear about that. But he hasn't done that.
Where is it proven that DeSantis is even running for President, much less seeking RINO support?
If DeSantis doesn't agree with and/or doesn't want to be associated with Paul Ryan, Karl Rove, and Chris Christie and their push for DeSantis while they simultaneously criticize Trump then he should say so.
The only thing I'm aware of is Richard Baris made a tweet that claimed ...
I've seen no confirmable evidence of what Baris said, and I have not referred to it here.
Thanks. DeSantis could do that, but I also believe that he shouldn't have to be put on the defensive, since there's no proof he's done anything wrong yet. When politicians are attacked, they don't have to respond to every attack, the term as I'm sure you know is "taking the high road" and I think it is perfectly understandable fo him to do that, until any actual evidence of collusion is brought forth.
I've seen no confirmable evidence of what Baris said, and I have not referred to it here.
There's another old saying, that "the burden of proof is on the accuser" and so far there doesn't seem to be hard evidence whatsoever of collusion going on. Trump or his supporters, of which there are millions, should be obligated to provide at least some proof, before Trump's attack can be justified, in my opinion. And even then Trump's attacks should be more focused about what his concerns are, rather than just claiming things like DeSantis is "just an average Governor" which I don't think anyone believes.
Unfortunately I expect Trump and his supporters to keep attacking DeSantis with no concrete evidence, and DeSantis to just keep taking the high road. Who that is working out better for remains to be seen.