Worried GP may refuse to provide fit notes as fiance can't speak to him, and he's not on meds

hi all,
I'm currently trying to apply for uc for my fiance and i. my fiance has urinary incontinence and depression and anxiety. I'm really at my wits end here, it's so difficult trying to sort it out for him as he is unable to do it himself due to his mental health conditions. I'm currently looking at the citizen's advice page and doing the 'to do list'. It says he will need a fit note from the doctor before being sent the uc50. I am very worried that the doctor will refuse this as he has been unhelpful in the past. My fiance last saw the doctor in march 2020, who confirmed his results from the urology department and told him that his urinary incontinence was most likely caused by his severe anxiety and left him with that. He was on sertraline when he saw the doctor, but around 3 months later stopped taking them because he felt like he was feeling a lot worse on medication, but did not tell the doctor, and still hasn't. Around 2 maybe 3 years ago he was also on propranolol for his anxiety and came off that too, and a few years before that on different anti depressants. The doctor has written maybe three or four fit notes signing my fiance off sick from work due to depression and anxiety (and back pain which the doctor also says is caused by his anxiety) between 2018 and early 2020 when he last saw the doctor, so it is a problem which has been ongoing for a while and a problem the doctor has been aware of, and he has (reluctantly) agreed to fit notes in the past. My fiance stopped work in march due to his conditions. I'm just very worried the doctor may refuse due to my fiance not speaking to him in a year, stopping the medication and also because it'll be me asking for a fit note (with consent from my fiance) as his anxiety is so severe he is unable to speak to the doctor. Is anyone able to advise on this?