Exporting AI images in Premiere Pro Project

Premiere Pro AI images - My 3-4 minute song looks and sounds great on the Workspace Playback, but it won't encode well in Medica Encoder.  The encoded file is 3,500,000 KB, and the AI images are jittery and pixelate as they animate in simple positional or scaling motion settings.  I think it might be due to the AI images (Adobe Stock) , since some normal video in the song encodes correctly or well.  Does anyone have an idea of what is happening or have a fix?  Thanks.