@pfrew
If you have extended your broadlog, you may have used different target mapping(and different storage for broadlog and tracking logs), but the code you used will only use out of the box target mapping, and OOTB recipient broadlog. Hence it was not able to add the data to OOTB broadlog which does not have those fields. You may have to update targetmapping for this winner delivery using jscode. Something like-
delivery.mapping_id=primary key of target mapping you have used for first two deliveries.