Dog Lover
I've had three males prior to the two females I have now. So prior to the "girlz" my experience for the past 20+ years has been with male V's. They were real rock and rollers and knocked the beejesus out of each other, and yes, they could be **** on other dogs. The girls have been a pleasant surprise in contrast.
This sentence is for your husband :
If you have no intention of campaigning Clyde and spending the thousands of $$$ required to do so, if his papers aren't impecable, with multiple generations of champions, Field, Show and Bench. If his conformation is less than perfect. Then there is no reason to delay getting Clyde neutered. If he has no future as a breeding sire, neuter him and be done with it. Get the hormones and testosterone out of the equation, and see what issues are still there. Neutering a male dog is no cure all, or panacea, but before he starts all of marking and roaming tendencies, nip it in the bud.
I have a dominant female at this time. She's from a real high powered gun dog line, and she can be **** on wheels. She's a hunting dog first and a pet second, she can't be any other way, so I have an idea what you're dealing with. It took close to 6 weeks just to get her to stop biting me.
Clyde will come along, he's just at an age where he's beginning to assert his independence and dominance. The jumping and neck grabbiing are a dog play thing to establish position. Had the Rottie wanted to, it could have switched the tables very quickly an Clyde, bit it didn't. Still though, you have cause to be concerned because the day he is corrected it could be a very expensive lesson for you also.
Keep working with him. Keep working him at the heel. Work at all the basic obedience commands. Keep him on a long lead at the park, and every time he starts that stuff move him in another direction firmly and quickly. I know that you want to cut him loose, but he's not ready yet. At minimum he should be on a check cord.
He's going to "get it" someday, just be patient with him but very firm. Don't give him a command unless you are in position to enforce it,and make sure every command given is obeyed and enforced, even if just for a moment, then released. Make it black and white with no slack. Don't let him start to make decisions for himself, he's not ready.