I think that is your best bet unfortunately. I suppose it might be worth contacting the county health department to make a complaint about unhealthy conditions but a lot of Washington counties are run by the good ol boys clubs, and they don’t like to enforce things unless it’s next to their properties. I pity the county official that has to come over there.

People just need to be considerate of each other.

He will continue to be a bully as long as it works for him. Unless you think he'll start shooting or something, the whole neighborhood standing up to him is what it will take.

If the stench is that bad, there may be health and safety regs being broken, and perhaps there are standards for the keeping of that many animals. Some agency out there somewhere looks into things like that. Your county sheriff might be willing to mediate for you as well.

Be more aggressive than him. Bullies hate it when the tables are turned and they are on the receiving end.