I have a CBS from the very same batch of trees as yours, same plastic tub from Todd, I acquired in 2017. I have not had any weird issues and mine is growing really vigorously, but I am doing things a little different:
I have mine overpotted in a deeper pot than yours. Not repotted since 2018.
The soil mix is Boon mix (equal parts akadama, pumice, lava)
I seriously overwater my tree. It sits in full sun with the deciduous trees and it gets water every day. It has never dried even slightly or missed a day in 5 years.
I give mine miracle grow full strength every week during growing months. My philosophy is generate tons of buds then slow it down when its time to show.
So I would suggest food water sun and neglect, assuming the soil is right.
Here it was as acquired:
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and this is it this morning
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