I think that is what this person is trying to do.
He/she is deliberately making Vansh come to the spot at the right time. This will slowly make Riddhima lose her trust in him. Afterall she is a human, and no matter what she says about her amar prem for her patidev, every human's first instinct is generally to survive.
The constant attacks on her life and Vansh reaching on time...coupled with Ahana's words and Vansh's mysterious ways of testing her will eventually make her lose her faith in him.
Nice observation ๐๐ผ