Sounds like she took to a dealership.
Oil changes on my '07 5.9L have run $90 to $120 depending on where I was at the time. 12 qts of Rotella, oil filter, air filter and fuel filter
Oil panned rusted....could be. Depends on how much road salt has been used.
Wheel bearings.........way too much just for R&R on wheel bearings.
They very well could be bad but that is just too much $$$.
Independent repair shop vs dealership. You will get better pricing.
Doesn't mean that oil pan and bearings don't need replaced, just a better price for doing them.
From an old vet......THANKS for your service. Thanks to your wife also!!