I understand your frustration about this apparent lack of attention to your issue. Although I cannot say for sure why your ENT did not mention this aspect of you nose. It is possible that your ENT thought that this was not a pertinent part of your clinical history. This is because a deviated septum is a physical exam finding rather than something that you ask about from a patient. I imagine that your ENT did do a thorough nasal exam. Thus I'm sure that he or she became aware of your deviated septum before making a final assessment and recommended treatments.
To answer your question, a crooked nose can be caused by something other than a deviated septum, but most likely, that is what you have. A deviated septum is very common and almost everyone's septum deviates somewhat to one side or another.
On a side note, if your deviated septum is a contributor to your sinus problems
(as it can be from time to time), then your ENT will want to correct this problem surgically before, during, or after you sinus operation (if this is what you are going to get done). Make sure that you and your doctor
discuss this aspect of the plan in detail before moving forward. Good luck.