Hi Rick
I guess you’ve probably solved this one or given up on it by now but I’ll leave this here for the record.
I was having a very similar problem With After Effects and Media Encoder. Immersive video effects were rendering fine in the AE timeline but rendering out of Media Encoder resulted in the same red warning bar. Which is weird because I had rendered the exact same project a few days earlier out of Media Encoder with no issue.
I finally managed to get it working by uninstalling then re-installing Media Encoder through the Creative Cloud app. I expect that doing this will also fix the problem rendering out of Premiere, although I haven’t tested it.