He did? How did he know that and when was he informed of it and by whom?
“How did he know that and when was he informed of it and by whom?”
That is not known at this time.
It could only be the people who were directing Hodgkinson to leave his wife and home in Illinois and travel to the DC area and stay for months with his guns and a huge amount of ammunition for no logical reason other than to assassinate the Republicans that Hodgkinson repeatedly said he hated and also said needed to be terminated.
He took many surveillance photos of the little known field and visited the location many times.
This was a planned assassination attempt.