2010 Sequoia oil pressure low

Looking for help/confirmation of my thesis, hopefully saving thousands in unnecessary repairs.

I've got a 2010 Sequoia with a 3UR-FBE, 260K miles on her, over here in Germany. Dealer has never seen one of these ever. Trying to assist so that i don't end up buying timing chains and other extras unnecessarily.

Been having some rough cold noises, been told it's lifters, unrelated, and not dangerous.

So I started the truck cold in about 10°F weather, dash lit up with 4LO blinking, check engine light on, and some others. Eventually noted the oil pressure indicator about 1/4 up, where it's always been midline (so half of normal). Didn't go into limp mode, and drove (I know) thinking it was just cold and would be ok. I became alarmed when the pressure indicator continued to drop near zero, with only minimal and temporary improvement with increased throttle. Stopped at a mini mart to grab oil, volume was not depleted. Drove straight to dealer for evaluation and repair.
They pulled codes P0015 and P0024.
Bank 1 camshaft B advanced, and bank 2 camshaft B retarded respectively. Timing at the chain level was universally intact on inspection.

Searching for answers, i found that older 4.7s had pressure transducer failures, but i reasoned i wouldn't get the cam failures if it was just the transducer. Finally looked up how VVT works, and based on direction of crank and cam rotation, if oil was not getting to the VVT system, they'd freewheel in the rear position, sitting advanced on one bank, retarded on the other.

By this reasoning, i conclude my issue is the oil pump or filter.

Was also told to look at camshaft seats for discoloration if truly a pressure failure.

Dealer here wants to change both of the driver side VVT sprockets, timing chain on that side, water pump, lifters on driver side, and to charge €10k for everything, that's after tax exclusion for military. They're not sure it'll fix things either.

Will likely cop for the water pump if the heads aren't trashed.

Can anyone let me know if I'm chasing the right rabbit? Again, trying like mad to pinpoint the issue and avoid shotgun purchases.

Thanks,

Peter