Migration validation error

I have run my Migration successfully

Found 23530 documents to update
23530 documents updated

subsequently:

Found 0 documents to update
No documents to update

The Unit Test runs OK:

Test Suites: 1 passed, 1 total
Tests: 1 passed, 1 total

But when I go into the Mflix Status page and run the migration button, I get “Migration: It does not appear that you correctly converted the type”. I have verified the test code is intact and replaced the sample data.

The server terminal (Linux) shows the action “GET /api/v1/movies/id/573a13a5f29313caabd1333a” after it crashes. I have verified this document and its date type lastupdated value in Compass.

I’m out of ideas. Any thoughts?