Every Dometic wh I have owned did not need an anode in the drain plug and Dometic stated it was not needed.
I'm not familiar with the term "in-line" water heater but I suspect they mean "on demand" water heater. You may find you are fortunate to have the more conventical unit especially in a Super C.
Now just find out how to turn it on?
2011- 351RLTS Eagle, MorRyde suspension/pin box,
2017- F350 6.7 PSD Lariat FX4,SRW, SB,CC
Hughes PWD SP-50A, TST TPMS
Gator roll-up bed cover
B&W Turnover ball, Companion Std hitch
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