Yes models must match, and it's trickier because there are often dozens of "levels of quantization" for each every model. But the particular model / quant-level expected can come baked into a version code-number or its own meta-paramater and be checked rather rigorously by asserting on the model-weight's hash at load time.

The opportunities are pretty wide in my opinion, but will take years and many researchers to ideate on. For example, take the Spaces Protocol below, the what, how, why of creating identities or address space on a blockchain took a decade from when the earliest of adopters started thinking about blockchain technology.

Basically if more of communications continues to go into/out-of/in-between LLM's there's this secondary "data layer" that can be hidden or exposed with ideas like this. There are freedrom and opensource concerns too since the major similar art is Google and the like developing internal system to watermark their model output: https://deepmind.google/science/synthid/