Variable loop to replace data populated with null

I am trying to get this loop to replace data within 3 columns if the schoolCheck is N. With the current set up it is working on daysAbsent only, when I execute the Variable Loop End, it then only works on attendanceAbove90Perc. When I step through the Variable Loop End it only nulls a single column.

Haven’t done much with loops in this regard, but if I can nail this down would be a very valuable tool in my toolkit, what am I missing here?

Appreciate any and all help

kn_example_replace_values_loop.knwf

edit: Some context behind this, I was given a data set that I need to join based on a concatenation of first and last name, as well as matching birth dates and school. Some students are matching but are not in any of our schools, which are the schoolMatch N students. I have already lambasted the stakeholder about not providing unique ids.