When I add filter to query the report goes in timeout

Summary:

Slow learning (WARF) query

Content (please ensure you mask any confidential information):

I have the attached query. Everything works just fine without the final where condition.

Unfortunately when I try to filter by date the wlf_assignment_records_f table I get timeout (I know I can schedule it but this is not the point). It happens even by adding just these 2 highlighted lines:

I also tried with these optimization option:

Any idea?

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