Hi @jwarren ,
Welcome to the eazyBI community! Thanks for posting your question!
I’m afraid you cannot combine two dimensions into one filter, however, you might consider a solution described in the community post here: Compare Assignee with Logged By and check ou tour Demo report using the same approach here: Logged hours by user on assigned and unassigned issues - Issues - Jira Demo - eazyBI. The solution will allow you to keep Assignee dimension in rows and return the logged hours against the Assignee user who logged the hours.
Best wishes,
Elita from support@eazybi.com