Hi and welcome
@Boatee
I'm type 3c following pancreatitis. I've been treated by insulin from the start and there was never any doubt that the pancreatitis caused my diabetes.
Are you taking Creon (or other digestive enzymes)? Generally 3cs also need Creon due to the damage to the cells in the pancreas that produce the digestive enzymes. Signs that Creon is needed are loose stools/diarrhoea due to poor absorption of nutrients (especially fat). There is a test (faecal elastase test) that can be carried out to see if digestive enzyme (PERT) treatment is needed.
In terms of reclassification the need for Creon would give an indication that you could have 3c. Also are you able to request a CT scan of the pancreas which would indicate the degree of pancreatic damage? That could also help.
It must be very frustrating to have this confusion over the type of diabetes that you have. Hope you are able to get things clarified soon.