In response to questions NJ received on this topic, the following was posted to their website.  The representative I spoke with previously called to let me know. So now the informal answer I previously received is official. 

How to Report Federal and State Differences on 2023 NJ-1065 from K-1s Received from Lower-Tier Partnerships

Some practitioners and taxpayers have asked about how to report the federal and State differences from federal K-1s and NJK-1’s received from lower-tier partnerships on the 2023 NJ-1065.

Please be advised that Lines 13b and 15e on the 2023 NJ-1065 are for reporting “other modifications” that were not accounted for elsewhere that are a State addition or deduction to income, respectively.

The corresponding difference between the lower-tier’s federal K-1 and NJK-1 is reported on line 13b if the net NJK-1 income amounts from the lower-tier partnerships are greater than the lower-tier partnerships’ federal K-1s. The corresponding difference between the lower-tier’s federal K-1 and NJK-1 is reported on line 15e if the net NJK-1 income amounts from the lower-tier partnerships are less than the lower-tier partnerships’ federal K-1s.