20 years ago our networking group was shown software for graphically tracking computers and other devices as they moved across campus. One of the objectives was to notice which devices were usually used together and to note when they were apart. It seems to me that in 20 years that has become much more sophisticated and applied to cellular devices.
The point is your burner phone will identify you if you ever had it turned on in the proximity of your daily carry phone. Even if you intentionally left your daily phone at home while you went out to set fires while carrying your burner phone.