I’m having all sorts of problems with my beasts in this game. I went looking for the rare striped wolf, because I have the other two, and successfully tamed it. However, I sent it away shortly after and was killed by a bear. Upon restarting, I didn’t have the rare striped wolf. I tamed it again, died again, and didn’t have it again. It was showing as being tameable in Oros even though I had successfully tamed it twice. The thing even attacked me later in the game.
I’ve also been attacked by both the regular and rare dhole. The regular one shows in my list as having been tamed but the rare doesn’t even though I’m certain I tamed it quite early on after learning how. More so now that the rare wolf attacked me after being tamed. This ‘Beast Master’ thing makes no sense to me.
This is on PS4.
The first paragraph is easily explained by Far Cry Primal loading the most recent (auto)save after dying, in this case one where you didn't yet tame the rare wolf.
After succesfully taming it, either save the game manually or fast travel to another location to let autosave kick in.
As for the second paragraph, it sounds like your issue is that the predators you once tamed are attacking you when encountered in the wild - this is normal.
Beastmaster or not, they will always remain hostile to you when you're not accompanied by a stronger tamed creature by your side. Just because you tamed one of their kind once doesn't mean they'll all be friends with you.