Sorry, took me a while to get back to this one
In case you haven't figured it out already, Biofusion Science requires the technology that allows you to drop cargo pods onto Rubia, as well as Gleba science, which means you must have already completed both planets to this point.
This means you have access to Gleba's iron bacteria processes (which are no longer surface locked once you unlock Biofusion Science) as well as the ability to drop cargo onto the surface of Rubia (where the Biofusion Science pack is crafting-locked).
I think you should be able to figure it out from there, just be aware of the iron bacteria spoil timer. Gleba Reborn is compatible with Rubia, and can be used to extend the spoil timer as much as you like (if you really need it).
