I don't understand the point.
Let's begin ...
I like the Steinway sound.
If the Pianoteq Steinway sounds like a real Steinway, then I will like the Pianoteq Steinway, too.
OTOH, if the Pianoteq Steinway is unfaithful to the Steinway sound, then I will dislike the Pianoteq Steinway.
Another person (with different hearing, and with a different Yanny result) might also like a real Steinway.
If the Pianoteq Steinway sounds like a real Steinway, then he will like the Pianoteq Steinway, too.
But if the Pianoteq Steinway is unfaithful to the Steinway sound, then he will dislike the Pianoteq Steinway ... just like me, despite his different Yanny hearing.
Yet another person might dislike the Steinway sound. (Heathen!) 🙂
If the Pianoteq Steinway sounds like a real Steinway, then he will dislike the Pianoteq Steinway, too.
Comment: The need is to compare real piano A with Pianoteq's version of piano A.
Conclusion: Yanny doesn't matter. This exercise is moot.