Work for Hire Dispute: NFT of someone else's art

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Illustrative scenario prepared by my practice.
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Hypothetical question

Using a throwaway bc my boss knows my main. Looking for advice on a legal issue. Here's what happened.

NFT of someone else's art. I've been dealing with this for about 9 weeks now and the situation isn't improving.

This involves software/code I developed over the past 33 months. I do have documentation proving my ownership and timeline.

Has anyone been through something similar? What worked for you?