Rorie...What meds. is your dad on for his Trigs.? Usually folks with diabetes do seem to have high Trigs, my hubby has both also. He was on Lipitor for years, but it did nothing for his Trigs., and like your dad, his TC was fine at 202. He had a lousy reaction to Lipitor and other statin drugs, so now he tries to control his numbers with diet and exercise. They are coming down, but slowly.
Does your dad eat alot of carbs. and processed foods, if so, that is very bad for Trigs. There are folks here who have battled high Trigs., so I am sure they will try to give you some helpful advise. Is your dad able to exercise, as that will also help bring down his numbers.
Hope U get some good advice, and good luck to your dad...