I have the opposite situation but it's working very well for me. I've got a therapist who started me on EMDR a few months into starting seeing her 4 years ago; it didn't go so well. I decompensated and started dissociating during sessions, I couldn't articulate much words during and had issues with slowing down the process because the images all were coming too fast and furious. I stutter anyway and I started to get very frustrated by not being able to talk when she'd ask what I was seeing during a session. I couldn't ground myself and I was getting suicidal during the rest of the week. I was a mess.
So she referred me out to a somatic therapist who's job it's been to teach me to stay in my body. I've been with her almost 2 years. (and my relationship with her is kinda rocky at the moment, but that's another thread based on her personal & professional life falling apart right now). But she's done fantastic for me. The somatic therapist I see weekly(ish) for ONLY grounding and resourcing in the here and now. We don't talk anything trauma related. She's working on getting me to expand my resiliency by guiding me through something a little upsetting in my everyday... then walking me back through grounding. Like blowing up a balloon I guess.
I still see both therapists. My original therapist is person-centered and knows my traumas. I have temporarily transitioned to seeing her every 2 weeks for the past few months (was seeing her weekly before that). We're holding off on resuming EMDR on positive resourcing for another few months before trying again.
The two therapists are aware of each other obviously, and they spoke at least 4 times about my care in the beginning that I do know of (but they are in the same supervision group, so I don't know if my chart ever comes up). So I don't know that they communicate ongoing. It was rocky and confusing at times in the beginning, because one therapist was telling me one thing and the other something different. But we made it work by not talking about the other in each other's session.
Eventually, my goal is to wean off the Somatic therapist (probably sooner than I'd like based on her present situation) and resume the EMDR on my traumas. I'm not quite there yet.
So not exactly your experience, but similar.