It seems to me that this is a golden opportunity for a lawyer.
Not allowed to pray in a public park? Not allowed to carry Bibles into a park? Not even allowed to cross the street and approach a park?
There’s not even a pretence that these guys were threatening violence or hate speech or whatever the latest liberal shibboleth is.
Amendment 1 - Freedom of Religion, Press, Expression. Ratified 12/15/1791. Note
Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech,