QueueProductionItemByPBG usage help?

I’m hoping this is fairly straightforward and I’m just missing it in the docs. I’m looking into queuing units on an event, exactly like the French Chamber of Commerce bonus works (Eco tech research queues a trader in the Chamber of Commerce. While spawning units seems to be straightforward (and an included example) enqueuing units is not.

I’ve attempted to use Entity_QueueProductionItemByPBG, but it’s returning false. My test usage is pretty straightforward, Mod_Start() calls my test function which grabs the current players TC entity id and gets a vills blueprint using BP_GetEntityBlueprint(). It then passes that to Entity_QueueProductionItemByPBG() with a ProductionItemType of ‘PITEM_Spawn’. It then returns false and doesn’t seem to do anything.

Not much showing up in the debugger besides expected values. I even checked to make sure the TC entityID I have has a queue (true) and that queue is available(true). Is this just not possible? Or is there something I’m missing?