Same problem here… any news when WD Discovery will be available in Finder?
Please refer to KBA 25994 to resolve the issue of “Internal Server Error” when sing in to MyCloud.com on macOS 10.14 Mojave
https://support.wdc.com/knowledgebase/answer.aspx?ID=25994&s=
What annoys me about this issue and this board is that yes you can see the drive now but it doesn’t even function at half the speed as it did prior to Mojave and WD update.
When is the official fix going to occur? Nothing works as it should. Great we can see it but I would love it to work as described and at this time it doesn’t.
Really disappointed with WD, they still have not issue an update for Mojave. I would advise mac user against getting WD product.
I am unable to even access my folders - it give me a timeout error wether i try and access it via MacOs or on the MyCloud website 
