Even better, I did this:
=IF(ISERROR(INDEX(Sheet2!$B$2:$E$11,MATCH(Sheet1!A4, Sheet2!$A$2:$A$11, 0), MATCH(Sheet1!K4, Sheet2!$B$1:$E$1, 0)))=TRUE,"",INDEX(Sheet2!$B$2:$E$11,MATCH(Sheet1!A4, Sheet2!$A$2:$A$11, 0), MATCH(Sheet1!K4, Sheet2!$B$1:$E$1, 0)))
So now no more ugly NAs and it only...