I found a workflow that makes a field mandatory on the case record depending on its assignment queue (custom). I discovered this is also affecting our case entry form in the customer center, which is not something that was intended. How can I make this field mandatory only for internal cases? Can you specify the centers?

You should add a condition to the workflow itself to exclude roles of customer center.

@Yadigar has it. Add in the conditions. I think you can also set conditions based on the custom form too, if that is the preferred route.

Hmm, I used

User Role != Customer Center

then logged in as customer from a test account. Still mandatory.

just throwing out an idea here... do cases happen to have a "source" field available on them? i know on my sales orders entered from the customer center they have a Source field that gets populated with "Customer Center" value, curious if that is available on cases as well

It was a custom center. We don't use the standard customer center. 🤦‍♂️