After Effects clips in Premiere no longer work with the morph cut effect.

[#1]

I've been doing this successfully for a few months now.  Suddenly, any time I attempt to apply the morph effect to any clip that has been replaced by an after effects composition (ie. green screen keylight), the morph cut produces only a jittery transition.  I have a major project ready to finish the transitions due this week, but suddenly it doesnt work.  

I have gone backwards in versions of both products.  I've cleared all caches and moved them to different drives.  I am using proxys.  In testing in a new project, I have 2 simple 30 second clips which morph together perfectly.  As soon as I replace both with an After Effects keylight composition.  The jitter comes back,  this is all new behavior.  

Today after updating to most recent versions, for the first time, when I apply the morph cut, I received a message saying: Insufficient media. This transition will contain repeated frames.

Attached is a clip showing the jitter.

[#2]

I've been doing this successfully for a few months now.  Suddenly, any time I attempt to apply the morph effect to any clip that has been replaced by an after effects composition (ie. green screen keylight), the morph cut produces only a jittery transition.  I have a major project ready to finish the transitions due this week, but suddenly it doesnt work.  

I have gone backwards in versions of both products.  I've cleared all caches and moved them to different drives.  I am using proxys.  In testing in a new project, I have 2 simple 30 second clips which morph together perfectly.  As soon as I replace both with an After Effects keylight composition.  The jitter comes back,  this is all new behavior.  

Today after updating to most recent versions, for the first time, when I apply the morph cut, I received a message saying: Insufficient media. This transition will contain repeated frames.

Attached is a clip showing the jitter.

[#3]

PS. I have chosen not to upgrade to MacOS Big Sur for fear it would break something critical in Premiere or AE until I can finish this project.  MacBook Pro 2019 16gb with AMD Radeaon Pro 4gb Graphics  

[#4]

Here's the way I work with AE comps:  I render out of AE in a highquality format and place this file directly above the AE comp in the premiere timeline.  Keeps things much simpler, speeds up outputs and avoids this sort of issue.  I know it shouldn't be necessary, but no reason why you can't work this way and get your job done...