You absolutely can go directly from LC to bulk substrate, with the only caveat being that your bulk substrate would need to be prepared similarly to grain substrates (sterilized, not simply pasteurized).
A close friend and I have been working for a number of years at designing a continuous flow closed-loop LC/synth-sub propagation system. The only real issue that you’re going to run into attempting to run a production facility off of a direct-injection cultivation pathway is 1. You’ll need a slurry homogenization step to ensure consistent flow/consistent inoculation loads, and 2. You’ll really need to have your sterile techniques locked in, and/or have a solid QC/QA plan and filtration pathways in place.
LC gets contaminated very easily, and contamination can be especially difficult to identify/diagnose in LCs (or anything really if one isn’t sufficiently experienced/educated in all the various possible contaminants and how to identify them)