Has anyone been able to route expenses workflow to the Principal Investigator on a project?

Summary:

We are trying to modify our workflow for expenses. We want it to go to the line manager of the employee, then the Project Manager, then the Principal Investigator. We aren't seeing Principal Investigator in the drop down. Has anyone found a custom way to do this?

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Version (include the version you are using, if applicable):

Fusion Expenses 23B

Code Snippet (add any code snippets that support your topic, if applicable):