Earnie-
I'm glad you found the links helpful! Yes, the ERR Cruise Commander M is a drop-in replacement for the stock DCDR; the only change is that the ERR unit does not need the external motor sensor, so the three-wire plug doesn't get connected to the replacement board. Also there is a ground wire found on the stock DCDR board which does not get reconnected to the Cruise Commander M product.
I was able to find the product page and installation manual (scroll down to the part about the SD-80 with Odyssey, as this applies to your locomotive) for the Cruise Commander M.
Regardless if you opt for the Cruise Commander M or the replacement DCDR, I highly recommend Boxcar Bill (one of the forum regulars) as the go-to source for the replacement parts.
-John