"We've been doing this for years and have never had a problem" doesn't make it proper. This can proper for other types of Forms 1099 when the form is issued to only one of an number of joint owners and the recipient must nominee a portion of the income to other joint owners, but there is no joint owner here. This is entirely your income due to being the only listed beneficiary. Except when the courts intervene to reform a beneficiary designation post-death, or you execute a qualified disclaimer (which is not possible if you have already received the distribution or you have missed the deadline), there is no legal way to cause this to be income to anyone but you.
