The source is Facebook? No thanks.
In the early 1990s: “I saw it on the internet. It must be true.”
Bygone times.
There’s a better chance that the guys who tried to kill the president probably had money funneled to them.
The source is "Jonathan Gregory". He posts on Facebook. His posts seem to remain uncensored on that platform, and they are mildly "Right-Wing American Nationalist" in general character.
There are a large number of people with that name visible in search results, and it is not clear that this person is really any of them. There are no definite indicators that he has contacts in the government who could leak the information that he is posting.
Is this person a reliable commentator with a track record of accuracy? I cannot tell. The DSA subsidy is a good story with a weak foundation, so far. I rate it as "low probability".
But it is the kind of thing an FBI supervisor with two trainees could confirm or refute in a day or two. Add an extra day to get a court order from a sympathetic judge. Bank records like that would be an open book for the FBI. And it would be worth checking out. I wonder what they really have found.
I wonder if they are telling their bosses what they have found.