Getting my dad the PET scan he need

It all started a few years ago when i notice a slure in my dads voice, of couse first thought is hes drinking again, but we all couldnt be more wrong. About a year ago he finally was able to get some test ran, MRI and CT scan coming back with nothing, dr.s would like to go a PET scan on the area of the brain that controls speech. So it was scheduled, one day before the scan the dr called and told him his insurance wasnt going to cover the scan. About a year has past now and his speech is more slurred and cant even really hold a conversation. Hes a hard working man who would give the shirt off his back for anyone, this just breaks my heart.Please anything helps