I don't have an answer but will be very interested in comments anyone has. I too am a curly whirly and getting a decent haircut, at times has become the holy grail. Anytime I have asked a shop if they have someone who is good with curly hair, the answer is always, all our stylists are good with curly hair. Not true!
Just last week I got a decent cut at a chain place and the first thing I told the stylist was I do not like thinning shears to be used. She looked at me quite surprised and told me, no one there would use them, EVERYONE knows not to use thinning shears on curly hair.
I really cracked up inside because I can't count the times stylists have come at me with the darn things, insisting that is the secret to controlling the curl. And one of the worst thinning shear incidents was done at one of their shops.
So, good luck with your quest. It is hard to stop someone in the process of cutting, but after decades of trying to find the decent cut and stylist, I have learned to speak up. Incidentally, I have had expensive and cheap cuts and it has still been difficult.