Kegels, honestly I don't really retain erections long enough without pharmaceuticals to do any edging.Have you tried focusing solely on stamina work to improve your EQ?
No offense, but it's likely that the medical professionals you're conferring with are lazy or (as you stated) aren't taking you seriously. Unfortunately, that's a very common response. That being said, even if you have a venous leak there are measures that you can take to correct it- as long as it's not too severe (see https://www.pegym.com/forums/penile-anomalies-injuries/10071-ideas-combat-venous-leaks.html). From what you describe, whatever you have likely isn't severe.
Yep I had a whole long thread on that frustration https://www.pegym.com/forums/erecti...nding-doctor-actually-interested-helping.html
I've talked with a number of guys over on franktalk that said they had to go through a bunch of urologists before they were eventually diagnosed with VL. A lot of them have penile implants now, but I don't think I ever want to go with that option.
I honestly think I have multiple things causing my ed. Physical (evidence for that is lack of nocturnal erections and non-response to injection). Psycological, and possibly hormonal as my libido is way down, although I did have a complete hormonal panel done twice and nothing clearly indicating hormonal ED.

