2023 CX5 Pre-Purchase Inspection – Wet Timing Cover?

Just bought a 2023 CX5 , 20k miles. Dealership gives 5 days to bring it back for full refund or 30 days to exchange.

Got a pre-purchase inspection and the mechanic recommended new tires, a new battery, and noted the timing cover was wet. Is the timing cover anything I should be concerned about?

Dealership said they’d fix it but I want to make sure I’m not getting myself into a big problem long term.

Also dealership said tires are debatable. Any advice on pushing back is appreciated too.