Hello,*
I have a crazy idea and I don't know if it's going to work.
Will a Castle Creations Mamba max pro 1/10 esc sensored work with a sensored tekin 1/8 gen2 brushless motor 2650kv work? All the information will be greatly appreciated! If possible please post pictures of the systems? Thanks for your time!

yes, no issues there. Use a BEC though.

I've run one of those through a $35 Hobbyking X-Car 120 ESC no problems, and more stable than Castle too!

It's been done before. You shouldn't have a problem