It could be the same issue, but it seems to be presenting in different ways and as such temporary workaround might be different. idon23's issue presents when there is nothing behind the items being faded - as such that is why I had suggested using a key color and then keying it out in post production. Your issue here is presenting when the items are in front of tangible geometry with materials applied - so the keying workaround won't be effective, unless you completely separate your animations from what is behind it, which would be a definite pain in the butt to have to do.
The issue causing both might be the same, but could be unrelated as well. With idon23's being that the parts are being faded over the environment, it's likely that it's a product of the light from the environment being white - despite the enviro being transparent, it still acts upon the geometry.
In your case, the objects behind it are acting upon it, so the part fading thru white makes no sense.
I haven not upgraded to 11 yet, so I couldn't do a test for you. Maybe Luxion has an answer for that. Also, put a ticket in thru their actual support site. You'll get someone actually addressing the issue vs. hoping they see it and responding thru the forum.
https://luxion.freshdesk.com/support/home