Why not "Salutationem in foro facio?"
Maybe salutatio is something they only do in front of the house of the patron, but i am not sure.
It also works (October, 2020)
Why is using "ego" here wrong?
It's not wrong, but it's placement might matter (in the database).
I think the problem is not with "ego", but with "patronus", which is in the nominitive case, whereas here the accusative case ("patronum") is needed. "I visit him", not "I visit he".