6-Max No Limit:

Suppose UTG opens for 3BB, and we in the Big Blind with perfect knowledge of UTG's opening range. Everybody folds to us. We know the "GTO" 3-betting strategy in this situation, so the only range left to construct is the calling range, as anything that is not called will get folded.

Now, want to find a game-theoretic calling range from the Big Blind. (I use the term "a" calling range and not "the" calling range because I want to keep things simple for myself at the moment, though I understand that our calling range will technically be unique.)

Suppose we guess a random assortment of hands as our calling range. Call this range C.

We use a perfectly accurate post-flop solver to solve for the EV of our range C vs UTG range across every possible flop. Ignore removal effects on the flop types and the ignore the effects of the other players at the table not having a hand to continue with. I.e. we are just solving for the EV's across every flop.

If our range C obtains an average EV across all flops (we are assuming equal probability of flops) which are appropriate to calling the raise based on our pot odds, does this mean that we "can" be calling this range?

I'm using the word "can" in two senses:

1) It would be dominated to fold any hand in this range under our assumptions (which do introduce an error), not in the sense that the real equilibrium strategy would be to call this range.

2) I have assumed that we know which hands to 3-bet so that we avoid some possible perversions in the solution (i.e. calling a hand like Aces distorts the EV of the range in such a way that with how I have worded the questions, we may "calculate" that we can end up calling very weak hands.)

The questions is probably a mix of some technically sound ideas and total nonsense on my part (as I'm not a huge expert on game theory), but any theoretical and practical insight would be appreciated.