The Sinaloa cartel as Most americans think of it doesn't really exist anymore.
The Sinaloa cartel is now 2 factions. The Chapitos (Ivn and his brother - the 2 not in US custody) and La Mayizas which are loyal to Zambada. Given that one of the Chapitos is responsable for giving up El Mayo Zambada to the US, it's an under statement to say these 2 groups hate each other.
As such, the Chapitos have aligned themselves w the CJNG while La Mayizas are allied w El Chapo Isidro w is the reamining portion of the BLO.
Thus as far as the "Sinaloa" cartel not moving Fent, that's not true. The Chapitos/CJNG are knee deep in it as well as La Mayizas. It's money and easy money. That's Why Colima is the Most dangerous State in Mxico. Port of manzanillo brings in the precursors. They both/all want that hub.
That's Why you haven't seen as many plazas getting light up in Mxico since mid 2025. They are using each other and now there's alot of coopersrion between one faction of the "sinaloa" cartel that's probs 65-70% of the old cartel with whats been the largest cartel since Chapos capture. They're learningto juice the routes the best possible and working together more so than probs since the original Guadalajara cartel back in the 70s/80s.
Heck, Tamaulipas has One If lowest murder rates in Mexico now. That's Not because Mexican govt did anything.