Pyanodon's Petroleum Handling removes the vanilla oil refinery and adds "heavy" and "light" refineries in its place (along with many other related buildings). This makes it impossible to produce Tiberium slurry, Tiberium Sludge, or to jumpstart Molten Tiberium.

Is it possible to expand the list of machines capable of producing the Tiberium fluids?

Oh yay, another mod that removes stuff there's no reason to.

But yes, we can fix it.

This is fixed in version 1.1.5
Molten Tiberium can now be made at the Light Oil Refinery and Liquid Tiberium at the Reformer (Tiberium Slurry was moved to the Assembling Machine in 1.1.5 regardless of which mods are active)