Earlier quoted context omitted.
But that's just the thing with open weights: you're not doing any business with company that made the model. They might publish the weights to a, say, European host, and then you download the model from Europe and and run it on your servers in America, and suddenly it's very hard to tell where the model was originally created.
Yep, add a few blank layers, fine tune it a tiny bit and the weight checksums nor parameter counts won't match with anything, while the model will be practically the exact same. Time and time again random startups have tried passing established open models as their own. "You made this? I made this." Of course a conspicuous architecture would still give it away.
You could even have another model watch the distillation process to check for goofy backdoors (which is about the best you're going to be able to do since detection of backdoors is np hard IIRC).