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The formula below will draw the average, disregarding the highest value in the range. Enter it in row 2 and copy down from there.
=(SUM(OFFSET(A2,0,5,COUNTIF(A:A,A2),1))-MAX(OFFSET(A2,0,5,COUNTIF(A:A,A2),1))) / (COUNTIF(A:A,A2)-1)
I can't give you a formula to do the highlighting. It should be possible using CF but I didn't find the way. The formula below extracts the maximum on the worksheet. (It's part of the above formula.)
=MAX(OFFSET(A2,0,5,COUNTIF(A:A,A2),1))
You can use a variation of the same formula in CF.
=F2=MAX(OFFSET(A2,0,5,COUNTIF(A:A,A2),1))
You can apply this formula to F2:F6 and it works well. Then I applied a variation of that to F7:F12.
=F7=MAX(OFFSET(A7,0,5,COUNTIF(A:A,A7),1))
That works well, too. But when one formula is applied to different product ranges, as is possible on the worksheet, it fails.