[Sporktacular]

This could be worth fighting for. If another maker uses your work to build and share an improved lock, as you did, this guy could try suing them for that, as though the basis for their work was his, ruining the spirit of openness and stunting any resulting improvement in lock design.

It might be a struggle to prove prior art but you might have enough sway to be able to find a pro-bono lawyer, and/or publicly pressure or embarrass him into compromising. Patreon would almost certainly help with costs too.

Seriously, you have a tremendous amount of credibility in maker/engineering communities, among others. Thank you very much for doing what you do.