Hi
@Macky1 and welcome to the forums.
Do you know what medication your dad is on? And what his hba1c is?
I ask because my father, diagnosed T2 in his 70s and now 92, never tests either. He moved onto gliclazide about 10 years ago before low carbing, then came off meds altogether when he stayed with us one summer and started to low carb. He has been recently put on metformin when his hba1c went a little higher (60 from low 50s???) . Generally GPs seem a lot more careful about putting older people on glucose lowering meds, because a fall from low blood sugar can be much more dangerous than a slightly higher hba1c.
I don't see the point of my dad doing blood tests at his age, as long as he gets a regular hba1c. He has a lot of medical conditions and (in my opinion, disclaimer I am not a GP) it's not going to be the diabetes that kills him (or even incapacitates him, he's not very mobile now because of long term back/hip issues)..
However, he does have his hba1c regularly monitored so if that showed a significant change we would review the situation.
Depending on your father's mental acuity, it might be time to see if he will let you view his medical results online. (I would very much like to do this for my dad, but he's of the opinion that it's too difficult to go to the surgery to fill in the forms). Unfortunately, while he doesn't in any way have dementia, his short term memory is poor and he tends to forget exactly what the nurse has told him.
Another thing to remember is that many of the people posting here are significantly younger than your dad and so may experience and handle T2 with a slightly different emphasis.