My own impression is to agree with 052rc's writing: "Mixing amps like what you're talking about almost never sounds right."
Here, there are some listeners who have found happiness with solid state, others who prefer tubes, and others who hop the fence from time to time. I would think that most here would agree that tube power amplification and SS power amplification are fundamentally different in character -- even those amplifiers at the highest price point and/or the highest performance point.
They are different; highs, lows, mids, sub-bass, impedance, phase, authority, slam, smoothness, stage, imaging, presence, air, on and on.
Bi-amped, approaching crossover frequency, one will hear two amplifiers contributing, more or less, the same amount of sonic energy. If the two sources of that energy are inherently different, then the result near crossover will be perhaps a strange amalgam.
I'd wager some readers have found likeable combinations, but none without much consideration and many experiments. The probability of "picking" one SS amp, one tube amp, and one speaker, and getting close to excellent sound seems quite small.
YMMV; please do report back in detail.
Cheers.