I thinks the plan was to send baby Rumple to a land without magic, like Snowing eventually do with Emma and the wardrobe. Tiger Lily even points out that Fiona’s solution would send ALL the children to the LwM.
Why wouldn’t they just use a bean? I mean this way before James destroyed all of them so they would have been hard to find but not impossible. She could have taken Rumple and herself to a land without magic.