I think you need to give them visiblity on how long it will take to review, test and understand how it works and the risks so engineering feels comfortable being on the hook for it.

I would not treat it as code to merge. It is closer to a rough spec that happens to compile.

Give them time, resource requirement and budget to get it done right. eg: I need 16 ppl, 2 mil and snacks for my cat. What non tech people bring to the table is extra resources. If they whip up whats required then who cares if prototype was vibe coded or drawn with crayons.