#1) Contact the local police, state/county prosecutor (to charge state crimes), FBI and federal prosecutor (to charge federal crimes). Press criminal charges....tresspass, vandelism, conspiracy, hate crimes, and, perhaps, "terroristic" threats. If found guilty, the "grown men" will be put in jail, community service, and/or pay fines to the government, etc. However, the grown men may be "let off" as it's probably their first crime. I just want to let you know that that is a possibility, but do not be detered from filing a local police and FBI complaint because of this "possibility". You have to get this incidence on record, as other incidents are more likely to follow if you do not.
I have found that each prosecutor has a mind of his/her own, and is not intimidated by the mob, gangs, religious headquarters, etc. I do not think the Watchtower Society will want to put its lawyers on this case, and will overtly disown these grown male bastards. It's bad press, overall, for the Society to be associated with "petty" type crimes. The Watchtower Society has spent too much money & time telling the average dub to "leave it to Jah and not take things into thier own hands", precisely for this reason. The Society likes to present a clean, law abiding, image, and blame the local members actions as isolated incidents it had no part of.
#2) Contact local attorneys, and proceed to sue each of these "grown men" in a civil court. A good attorney will think of multiple claims, such as tresspass, emotional distress, etc. The attorney may take the case on a contingency basis (meaning you will not have to put any money up front). If you win, you'll get MONEY. A builder and a plumber sound like some deep pockets!
Remember, OJ was found "not guilty" in a criminal court (option #1) but guilty in a civil court (option #2), and had to pay the families MONEY. It's easier to find someone guilty in a civil court, than a criminal court. But, I'd go for both as it sounds like you have good evidence and a neighbor willing to testify.
Skeeter