Great post as always, Tom.
If you look more closely both lines
AND corpdata.ArrearsRpt.recOffc = t-officer.t-ofcCode
AND NOT can-do("IN251870,IL063128,IA065464,IL070155",corpdata.ArrearsRpt.recOffc)
refer to corpdata.ArrearsRpt.recOffc.
kasundha should check t-officer.t-ofcCode against the list...