They're incentivized to classify whatever they can as not being their problem, so it makes sense for them to double-check everything - there is always a possibility that some edge case was found that lets them off the hook for some specific test or treatment. Moreover, obscuring information and spreading support staff as thinly as possible means that extra barriers heavily discourage people from fully knowing what they'll be on the hook for, which makes them more likely to just nod their heads and do/pay what is asked. These decisions aren't driven by medical concerns. It's a universal problem of nearly all kinds of privatized insurance - their core incentive is to ask for as much money as possible and provide as little in return as it's legally feasible.
The place where I live is often used by Americans as the first line of defense to justify their healthcare system. Among certain political circles, there is almost a reflex to point at us and say "see how terrible it is?!" by exaggerating all the drawbacks and minimizing all the upsides. Yet even in such a flawed, underfunded, mismanaged system, my government insurance plan covers all "medically necessary" lab testing, with a couple rare exceptions that are only covered if you're diagnosed with certain conditions. The process of getting a test consists of a doctor filling out a standardized sheet, then going to a lab and handing them that sheet and my regional insurance card. No money exchanged.
They couldn’t answer if cholesterol test would count. How is that not automatically classified as preventative? It’s one of the most basic metrics.
So they want me to get the doctor to give me the ICD code and the diagnosis code. Or something. Two different codes. They’ve added so much bureaucracy and crap into the system because they can. Nobody’s stopping them and there’s too many fingers in the pie.