Using this script in ModTweaker2 1.7.10 v0.7.5 / MineTweaker3 1.7.10 v3.0.9C / Forestry 1.7.10 3.4.0.7:

mods.forestry.Squeezer.addRecipe(100, [<minecraft:iron_ingot>], <liquid:water> * 1000, <minecraft:bucket>, 40);

The recipe gets added according to NEIIntegration 1.0.7, but the Squeezer doesn't accept an iron ingot as input, so it can't be used.

The issue is basically that we do this, which is the equivalent to this, but we don't also do anything equivalent to this, so this logic will never succeed when called from here.

Fixed in cf3ce11