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If a PT is not viable given your tabular requirements and/or result being non-numeric value (ie not viable in PT data field) you can adjust the previous formula as so:

=LOOKUP(REPT("Z",255),CHOOSE({1,2},"",INDEX('All Incidents'!$D$1:$D$1085,MODE(IF(('All Incidents'!$D$1:$D$1085<>"")*('All Incidents'!$O$1:$O$1085=1)*ISNA(MATCH('All Incidents'!$D$1:$D$1085,$E$10:$E10,0)),MATCH('All Incidents'!$D$1:$D$1085,'All Incidents'!$D$1:$D$1085,0))))))

Committed with CTRL + SHIFT + ENTER

The alteration is in red - and obviously reference to 1 can be altered to be a cell containing value of interest.