India will keep taking USD, because trade with the US is over $100 Billion USD: we're talking, "India must disband its entire military to offset the loss" levels of money. And that's assuming the US doesn't pressure others to avoid the INR, which would tank its value from the uncertainty alone, at least for a while.

It makes far more sense for India to just subsidize Egypt by allowing it to use INR to buy goods cheaper than with USD, rather than not taking USD.