You're asserting things I'm comfortable you cannot prove. Maybe you'll surprise me. But it'll require some work to even get at the issue.Parallel descriptions don't erase the author's logic. Hebs 3 uses multiple terms rebellion, sin, hardness, disobedience, to describe Israel's departure, but the writer still distinguishes the root from the expressions. That's why he ends with 2 different summary words: apeitheia (disobedience) in Vs.18 & apistia (unbelief) in Vs.19. If he meant definitional identity, he wouldn't use 2 different terms & Heb 3:12 explicitly gives the sequence you're denying: an evil heart of UNBELIEF leads to departing from the living God. The departure is the result, not the definition. The warning is aimed at UNBELIEF, not performance.
Jesus says UNBELIEF is what dooms a person: if you DO NOT BELIEVE that I am He, you will die in your sins (Jn 8:24) & the Holy Spirit sealed believer can never return to UNBELIEF, because God Himself keeps them, indwells them & guarantees their final redemption. (Ehp 4:30)
If Jesus accepts the sinner, the Father seals the sinner & the Holy Spirit indwells the sinner, then the only way that sinner could be lost or walk away is if the Trinity fails & the Trinity does not fail.
The argument in Heb3:12 is really a grammatical one. I've looked at the major grammars for this infinitive construction and they do not support a cause-effect interpretation, which you're freely inserting wherever you please.
The commentaries are all over the place as usual. I've never relied upon them or used them much. The English translations about the same and I only look at them for reference.
I'm probably going to stop paying attention to most of what you say. It's just too much eisegesis in support of an errant system of theology.
If you want to discuss why I don't think Heb3:12 says what you assert, I may join you, but I won't move all around with what I view as eisegesis. We'll need to dig in at one place before we move on.