Sorry, but I'll try to make my opinion the least negative as possible:
Where, and what, (else) did the Property Manager do, besides make 1 suggestion, how YOU can do some managing on your own ? Or, actually that was plural, so it's an active Management Team ? Great...(no, not really). Perhaps you could MOVE, after documenting your communication, re: 'Property Manager Obligations'. But don't start no war there; just check with an actual Attorney, what you could document, on your way out.
I'm thinking: 'Pesticide Bug Spray'! Mentioned once.
So that's STILL going on (strong smell) ? I'm not a chemist, nor Attorney. Maybe County Health Dept. as they have health and safety people, to suggest or run whatever test if needed.
But what I noticed, straight away: You enter another space, knocking on doors like that. Once is an appropriate action, maybe newly. But neighbor guy seemed immediately expressing concern...that's not your space, at his door (repeatedly). I made that (slightly) pompous assumption myself, in the past, and you've said he "refused' your REPEATED contacts, knocking on his door there. Oh yeah and "After 8:30", again according to your rules of conduct.
Doesn't make you a bad person, but, like I did, out of line. Heck, maybe just see, maybe a change, move to a nicer area, cheaper rental deal (with actual Property Management), and don starta no wars.
As to EMF;. I've seen Engineers go for that (hoax), hilarious, almost, watching metal 'grounding' plates get installed...under each electronics work bench. (They then re-installed the wood benchtop surface over the 1/8 inch plates). That was my Engineering Dept boss, letting the EMF consultants run amok.
Kinda funny, now, but he was incompetent.