Bug: `user_list_contributors` data has empty username fields

[jpmcb]

Describe the bug

I've found a few user lists that have empty "user" rows:

Notice the empty user row: that URL points to https://beta.app.opensauced.pizza/user

This seems to be because they are missing the username field (or at least that's my best guess right now):

^ that's on beta. But I also see similar results in prod.

Steps to reproduce

Not sure how to re-produce from the frontend side ... requires more investigation

Browsers

No response

Additional context (Is this in dev or production?)

No response

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