I do not know why other posters consider this to be none of your business since your nephews are disabled and clearly you were (potentially still are) their guardian. I am not sure that what your wife did in manipulating them into giving her (and her daughter) ownership in the property was not a criminal act. They are certainly vulnerable adults.
I do think that you should consult a local attorney.
Remember, this is the dude begrudging the $10,000 a year in disability, saying his nephew spends only $40/wk. As with people who complain about child support, he is forgetting that his nephew is housed, eats, wears clothes, etc.
Additionally, since the nephew has qualified for disability, there are severe limits on what he can get $/month. It is likely the wife has set something up so that any income from the house does not adversely affect her nephews benefits.
OP has come here, belligerent about his wife, but it sounds a lot like a stb ex complaining about cs.
I don't care about what he's claiming about his wife's "manipulating" his annuity on page 2. This is again vague enough that one can't discern if she is doing something valid or malicious. The lack of specifics make OP sound like an angry person with an axe to grind.