I would call the neurologist and let them know whats happening and that you're not getting the answers you need. Relate to them that you feel waiting for 2 MORE months to be seen is unacceptable and you may need to take him to the ER if hes not seen sooner, as then they would be forced to see him. If that doesn't work call your primary and tell them to call the neurologist and get him a sooner appointment.

I'm an RN, and I will not diagnose without seeing your father, but suffice it to say that his labs are concerning, especially mixed with the symptoms your relating, and need to be addressed before 2 MORE months have passed. If your PCP doesn't answer the phone, GO TO their office, cause a little scene if necessary. Believe it or not, I've had to do the very same to advocate for my patients before. It's even more effective when it's the family.
It's possible the confusion is simply from a urinary tract infection, but it's possible it's due to something more concerning. Regardless, it needs to be addressed.