I didn't really bother trying to follow most of your comment but pretty sure 2 is the minimum amount of questions needed.

1 to find a non random guard, since any answer the random guard is useless.

Once a non random guard has been determined, the 2nd question determines the correct door.

determining a non random guard is a bit tricky, but if you asked this to guard A, "if I asked you if guard B is random, would you say yes?", then list all the possibilities to this question, you will find that you can always determine for sure 1 guard that isn't random.

e.g. if guard A always either tells truth or lies, it doesn't matter which, then an answer of yes means guard B is random and C is good, whereas an answer of no means guard C is random and B is good.

if guard A is random, than both guard B and C are good, and you can ask either guard the 2nd question.

so first question goes to guard A, and with an answer of yes, the 2nd question goes to guard C, and with an answer of no the 2nd question goes to guard B, in this way, you've always picked a guard that doesn't give you random answers, and then the 2nd question is just "if I asked you is this the correct door, would you say yes?" and you're done.