Hi! Currently there is no support for modded recpies for landfill alt craft versions, so maybe you can add it?
I find this ones:
Cultered Soils from gleba_cultured_soil
landfill from soil from Dea Dia System
landfill from Externed Vanilla: refining
Landfill from crushed stone from Muluna

Not sure if they will be added but I will check them out. Thx!

i asked 2 other mod creators about adding alt ver of crafting concrete (https://mods.factorio.com/mod/concrete-productivity-modified & https://mods.factorio.com/mod/Paracelsin) and they both implemented it, maybe you can ask/see how they added it, so it will be easier for you