IMT CDL will be a better option for pursuing a correspondence MBA course. The curriculum is updated according to the latest industry trends. The course material provided is good and weekend classes are scheduled according to the academic calendar. The MBA course is rigorous. You will have to put in the required effort to score decent marks. Also, IMT has an excellent brand presence in the industry. The alumni connections can help you a lot in job hunting.
The correspondence courses are not worth it. They do not do any justice to the course. It is more about the brand value than the course. The correspondence course(s) may appear promising to potential employers who are ignorant or aspiring students who are in a bubble.
Getting into a regular MBA from either institute is something you should prioritize as it will bear fruits; more than correspondence ever will.