As far as I know my ISP isn't blocking anything. I have inbound and outbound NAT set up on my router so those ports should be fine.
As far as what's working, I can connect to the server on my lan using port 7707, and I can view it in the steam server browser using the query port 28852.
If I try to connect/query using those same ports on my public IP (or through my DNS that resolves the address correctly) I haven't had any luck. I also can't see the server in the ingame server browser but I'm sure that a symptom of whatever the problem is. I'm kind of at a loss because I have a reverse proxy set up through letsencrypt and duckdns and have had no problem connecting to the service that I have running on it. Is it possible that letencrypt is affecting something? I think my IP is dynamic but even using the DNS doesn't seem to help.
Also, I tried hosting another server (sven coop) and ran into the same problem, was able to connect/query locally but couldn't access the server on the public IP after forwarding the required ports.