Bond company requires citizen as administrator. So you as a green card cannot get a bond.
The bond company suggest you ask a citizen friend as an administrator. But they also want a lawyer involved.
In this situation, you have two choice
(1) ask the judge to drop the requirement of the probate bond because of your non-citizenship status, as well as you are the mother of the heir, there is some assumption of fiduciary dependability. Of course it's better you provide witness or supporting evidence to show you are dependable and careful, such as gainfully employed, highly educated etc.
Or
(2) you will have to step aside and ask a citizen friend to act as an administrator. That way a bond could be purchased. I think you have to try this first, before asking the judge to drop the bond requirement. You'll have to show that there is no plausible alternative (such as the ex has no family member, no close friend suitable). You don't have to show you don't have friends/relatives, because it is your ex's estate, as long as he has no relative/friends living nearby it is enough to show there is no plausible alternative administrator.
This is the best I can come up with, I am not estate lawyer so this could be all wrong.
