Bug: Using the Divide command on an edge feature with the target layer set to a junction feature class subsumes orphan junctions
Running the Divide command on an edge feature that has an orphan junction on at least one of its ends, with the target layer set to a junction feature class, causes the orphan junctions located at the end points of the edge feature to be subsumed by junctions from the target layer.
This is a known issue.
There are two options to workaround this issue:
Set the target layer to the orphan junction feature class, and then subsume the new orphan junctions created by the Divide command.
Delete the junctions inserted at the ends of the edge feature. This causes orphan junctions to be inserted at the ends of the edge.