I am sure that chase video was originally used by the Indian media to claim it was their Mig21 chasing an F16. It is far too grainy to allow any conclusive ID of the types involved.
However, the video posted below that tweet with two parachutes is extremely convincing evidence to suggest a twin seater got splashed.
The suggestion that the second chute was the seat stabilisation chute does not stand, as such drag chutes are very small. See below an example in action.
If you can see the drag chute, you will also be able to positively ID the ejection seat as the seat is bigger than the chute.
Furthermore, such a small chute cannot effectively slow the descent of the ejection seat, so even if you did see it, it won’t be drifting down as shown, but rather a barely slowed plummet.