I've only caught up reading part way but I'll wade in here.
I really don't care whether we talk about psychological hedonism or hedonism or whatever.
What I come back to is that Epicurus said living creatures pursue pleasure and flee from pain. Stop.
That's why pleasure is the telos. It is the thing to which all our actions and decisions terminate. Ask enough questions, drill deep enough, and everyone should/has to admit that the reason they did something was it thought it would make them feel good, it would bring pleasure. One can obfuscate, use fancy virtue-laden rhetoric, lie to oneself and others consciously or subconsciously. The result is the same. Epicurus calls us to pursue pleasure consciously and deliberately and to question our decisions in light of this guide that Nature has provided. Culture and society provide innumerable avenues that claim to provide us with pleasure or dictate what we "should" do. Epicurus calls us to question our culture's "that's the way things are done."