I wouldn't do that at all, bereavement fare is book into Q class. If someone just need to go immediately, just search for the lowest fare of all airlines.

I do have a question for the OP, since your grandfather pass away already, does it really need to go immediately ? Unless it had already secured the funeral arrangement, which it may take for a while. Find out the exact date you need to be there, it may save you a lot of money. I had been in the same situation before. There is a big difference in price between leaving the next day rather than in 2 weeks. I was able to get W class fare which is much cheaper than Q class.