I really don't do dog parks. I have enough that if I want my dogs to play together, I let them in the yard together. That works really good with two dogs that are compatible. Today I let three bitches out together.
Not randomly, I have let Karma out with Lassie and Lassie out with Hepsi, and Hepsi is two and really submissive. Karma and Lassie are both one. Mostly it went ok. But there is some ganging up, and it is the submissive one that seems to get targeted.
I think that you should leave before your dog chomps down on a submissive dog's neck. Because you say, that is over the top and aggressive. So if there are two dogs there, and you dog is doing fine, fine, but if a third dog comes, call your dog and go home.
Not all dogs are good at the dog park, and your boy is a teenager, intact, and has his hormones raging.
Jenna, RN CGC & Babs, CD RA CGC HIC
Heidi, RA CGC
SG3 Odessa, SchH1, Kkl1, AD
Ninja, RN CGC & Milla, RN CGC
Joy, Star Puppy, RN CGC
Dolly CGC & Bear CGC
Hepzibah & Hannah