Using Lookup IIF in conditional Formatting

Question

I need to highlight the dates that are in another dataset, this date is 90 days from a renewal date, ive used IIF(LOOKUP, but getting nowhere, this is what i have used

=iif(
LOOKUP(Fields!PERSON_ID.Value,Fields!DESTINATION_BASE.Value, 
Fields!THREE_MONTH_DATE.Value,
 "safe") = dateadd(dateinterval.Day,-90,Today()),"YELLOW","WHITE")