Welcome to the forum
Unfortunately the dealer is right. Key codes are not recorded, but there is a solution. If the compartments have a round silver lock, odds are they are a CH751 key, one of the most common keys for RV’s. As for the entry lock, you can buy a complete lock set from the dealer for about $35.00 and I bet he would be willing to use his “pass” key if the door is locked. If it’s dead bolted, you will have to drill the lock out. If the unit is “keyed alike” for the door and compartments you can still get a new key IF it ISNT deadbolted. Just have the dealer use his pass key, take the inside plate off the lock set and the code will be on a label.
Hope this gives you a starting point. There are a couple of different compartment locks, if you can post a pic, I can make an educated guess hat key it is.
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2012 Copper Canyon 273FWRET being towed by a 1994 Ford F350 CC,LB,Dually diesel.
Airlift 5000 bags, Prodigy brake control, 5 gauges on the pillar.Used to tow a '97 Jayco 323RKS.
Now an RVIA registered tech. Retired from Law enforcement in 2008 after 25+ yrs.