Expression expected error

SSAS and SSRS
1

I'm getting an "expression expected error" on the following. I can get each desired result in separate expressions, but I am trying to combine them in to one:

=IIF(Fields!Type.Value, "DataSet1" = '61',FormatDateTime(Lookup(Fields!ProjectNumber.Value, Fields!ProjectNumber.Value, Fields!VerifiedRP.Value,"RentalPermit"),2), FormatDateTime(Lookup(Fields!ProjectNumber.Value, Fields!ProjectNumber.Value, Fields!VerifiedOI.Value,"OtherInformation"),2))

Here is the IF, Result 1 or Result 2 broken out:

=IIF(Fields!Type.Value, "DataSet1" = '61',

FormatDateTime(Lookup(Fields!ProjectNumber.Value, Fields!ProjectNumber.Value, Fields!VerifiedRP.Value,"RentalPermit"),2),

FormatDateTime(Lookup(Fields!ProjectNumber.Value, Fields!ProjectNumber.Value, Fields!VerifiedOI.Value,"OtherInformation"),2))

I have been striving to fully understand working with multiple databases.
Should I use a switch function instead? Thank you guys.