500 Error creating a submission, version 3.4 upgraded from 3.2 and 2.x

Describe the issue or problem
On creating a new submission, I’m able to walk through the process until the final step, when I get a throbber that seems to run forever. In the Javascript console, I see an error:

Uncaught TypeError: right-hand side of 'in' should be an object, got undefined
ajaxErrorCallback https://revuesim34.libraryhost.com/js/build.js?v=
    error https://revuesim34.libraryhost.com/js/build.js?v=

This 3.4 instance was upgraded from 3.2, which began as 2.x.

During the 3.4 upgrade process, there were a number of orphan records that were cleaned up, and I’m wondering if those could have any effect on what I’m seeing now.

Steps I took leading up to the issue
For example:

  1. Login, Go to Dashboard
  2. Click on “New Submission”
  3. Go through New Submission process, including attaching submission files
  4. On final submit, receive error message as detailed above.

What application are you using?
Firefox 121.0-1, Ubuntu Linux 23.10

Additional information