Test matches are allocated by rotation. It was UPCA's turn to host the test. They chose Green Park. FYI Green Park hosted a test match in 2021
You really think Shukla is that powerful? He is a congress politician. I doubt anyone here will even know who controls UPCA and why Kanpur is important to them.
Sawai man Singh stadium doesn't host test matches. It hasn't hosted a test in 3 decades.
Right now RCA is building its own stadium, which will be ready next year.