Success!
Never found anyone who could tell me where these fuses are in the etrek 2015, but I did find a couple of folks who confirmed it likely would not be with the other fuses, somewhere inside, maybe under the dask?
But the fuse box for MB Sprinter vans where all the circuitry to the back is funneled and it's on the driver side step wheel. So I figured it would be smart to put these webasto fuses near there. And by golly I found the 3 fuse box under the seat -- push the seat forward so you can reach in the base behind real fuse box where they wired it in..
Once found, the reset process pulling the fuses to do the reset worked fine and I'm up and running.
