My experience with fina has been purely positive, but I understand that others can have a rough time with it.
I will say though, the vast majority of men have more than enough DHT in their system to be totally fine when taking fina, which reduces DHT by 70% at a full dosage. If I were the OP, I'd actually drop the tren entirely, replace those mg's with test, and just stop with the bullshit 19nors.
For the 1000's of threads we see on here were a 19nor destroyed someone's libido, it blows my mind that recreational lifters even use them. In fact, if you compare the volume of those threads vs the volume of threads where fina + test killed someone's dick, it isn't even remotely comparable. The latter might not even exist. In the literature, there actually isn't a palpable difference in the amount of people who reported ED from fina and the placebo group. ED from fina is so extremely rare, it wasn't even considered "real" for quite some time.
Is it possible? For sure. But what's the most likely culprit? 100% the tren.
I mean, on cycle, the solution isn't even difficult -- flood your body with enough test to outcompete the 19nor metabolites, but the OP doesn't like that answer, lol. The real problem starts when guys are off cycle or cruising and those demonic little 19nor metabolites are still circulating, binding to random receptors, and fucking everything up when you don't have the option to blast test.