I thought California was the main reason for the whole DEF system in the first place. It'd be a shame if it wasn't compliant...
That being said, try googling 'how to make my RV California compliant'. I got several hits, one which states there are smog testing stations that can test your vehicle. There was also a provision I saw that I your vehicle is less than 6 yrs old, you might be able to pay an abatement fee and still get registered. Anyway, it's a start. Let us know how this turns out ( not that I plan on moving to CA
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