For the most part I don't think router makers also made their collets. I think most of them outsource collets. I've found some crossovers. For example there are over 20 models and several brtands of routers that use a collet made by Accurate Electric. Bosch, Hitachi (M12V2, VC, and VE models), and many DeWalts, and there may be a few others. An old DeWalt 610 I have appears to use a collet that was designated as a Bosch WK style. My older Hitachi (M12V) uses a collet that I think an older Makita also used.
So there is a possibility that there were other routers that used that collet but I can't say which ones that might be. If you look through pictures on sites that sell collets like Elaire for example you might see one that looks like yours and if it looks like it then I'd bet that it is the same one since there seem to be a limited number of suppliers.
Someone I consider a master woodworker once told me that a master woodworker is not someone who never makes mistakes. He is someone who is able to cover them up so that no one can tell.