If Isna vlookup help

I have this formula, but would like to add to it and having some trouble. What I'd like to do is ad to the if statement that if in the ItemCodeCompare.xlsx the cell in column E has StarReq* in the cell, it would put the intire contents of the cell in ItemCodeCompare (ie. StarReq39279 or StarReq2656, etc.) I've attached some dumbed down excel files for reference. The WorkingFile.xlsx has the following formula in column F.

=IF(ISNA(VLOOKUP(A91,'C:\Intergraph Software\BOMtoBOQ Macro\BOMtoBOQ Macro\[ItemCodeCompare.xlsx]Sheet1'!$A$1:$G$65536,1,FALSE)),"CODE NOT FOUND",SubFab!$K91&"-"&VLOOKUP(A91,'C:\Intergraph Software\BOMtoBOQ Macro\BOMtoBOQ Macro\[ItemCodeCompare.xlsx]Sheet1'!$A$1:$E$65536,5,FALSE)&"-"&VLOOKUP(A91,'C:\Intergraph Software\BOMtoBOQ Macro\BOMtoBOQ Macro\[ItemCodeCompare.xlsx]Sheet1'!$A$1:$G$65536,7,FALSE))

Thank you!!!!!