Our only channel that works is referrals from clinicians. How do we find one to partner with? I will not promote

I will not promote. I'm a co-founder of a practice management platform used by therapy clinics that work with children with developmental conditions. Small team, two engineers. We both spent years on the IT side of this field in the US, saw how the incumbent tools work and where they fall short, and are now building something shaped for Europe instead. We have a handful of paying clinics in Eastern Europe and a few trials running in another European market. Every conversion we have closed came from a warm introduction inside a fairly tight professional community. Nothing else works: - Cold email: near zero reply rate across a few hundred sends, personalised and not - Calling public clinic numbers: I reach reception, never the clinical director or operations lead, and messages do not get passed on - LinkedIn: meaningfully better than both, but slow and capped by how many people one founder can credibly warm up at once We know the product domain well. What we do not have is standing as practitioners in this market, and that seems to be what actually opens doors. The referral channel works and I cannot scale it, because the person doing the vouching has to be a clinician, and that is not me. So the plan is to bring in someone from the field who is well connected and wants a stake in something, not a job. We have revenue but not enough for a senior salary, so this would be equity, commission on what they bring in, or some mix. I am fine being generous with that for the right person. My actual question is how you go about finding them. The people who would be perfect are practising clinicians, not job seekers. They are not on hiring platforms, they are not answering cold messages from vendors, and the ones with the best networks are the busiest. Posting "looking for a co-founder" feels like it filters for exactly the wrong person. For those who have found a domain-credible partner this way: - Where did you actually meet them? Conferences, professional associations, existing customers, alumni networks, something else - Did you approach it as a partnership pitch from the start, or start with paid consulting or advisory work and let it grow into something bigger - Has anyone recruited from inside their own customer base, and did that create problems - How did you screen for someone who will genuinely open doors rather than someone who likes the idea of being involved Interested in how this went for anyone who has done it, including the attempts that did not work out.