You can sort of cheat with text fields...
You can use MAX/MIN aggregations on them, but it's not often "meaningful" but rather arbirtrary alphabetization...
Still, I think in your case here, it works:
IF MAX([Product Type]) = 'Type 2'
THEN [SUM 2]
ELSE [SUM 1]
I attached your workbook.
test.twbx.zip 38.2 KB