Priority Splurger combined operation issue

Following a Suggestion post, I’ve attempted to make an indicator to show any imbalance on a connection. I’ve made an Outpost that has two setups, one with 2 priority splurgers, one as a priority splitter and the other as a priority merger, the second using a single priority splurger. The first two examples use the first setup and successfully show a shortage from the source and an excess to the destination. The last two examples use the second setup and do not show the imbalance - should this work?

Screenshot attached.