Pay for doing commercials in the 50s isn’t comparable to later years. She probably got a pittance. Now, if they used her recipe and had a contract, the company should be OK, if not, there’s probably a good settlement in store for those young men and other relatives. Quaker Oats (and other publicly traded, consumer oriented companies) can’t take too much bad publicity.
I suspect they really are trying to get some kind of settlement out of court and they write a check to get them out of their hair.