Looking for ASR / Whisper engineer for success-based partnership

I want to clarify exactly what I am trying to build. The goal is a production-ready ASR model for Heimish / Hasidic Yiddish, with strict, word-for-word verbatim transcription in Yiddish (Hebrew) script. The model must at minimum match the quality of an existing website that already provides a similar service, and it needs to go beyond that level. I am prepared to invest significant effort on my side in preparing high-quality, consistent transcripts according to agreed standards. However, I am only willing to pay if the final model demonstrably meets this defined benchmark. If the model reaches the agreed level on a fixed test set, I am prepared to compensate you generously. If it does not, the project stops and no payment is made. The final system must be production-ready and capable of transcribing audio in seconds, from short clips to long recordings. Because of this, I am not looking for a typical freelance engagement, but for someone confident enough in their ASR expertise to take on a success-based partnership for this project. If this aligns with how you work, please let me know what structure you would propose.