About dc and ex-fil's will?

[pinotnow]

Ex fil died last year and ex inherited as the sole inheritor. I have an on-going case with ex about CM arrears and his lack of ever paying for anything. As a result I looked at a copy of the will online and was shocked to see that if ex had pre-deceased his father then the money would have gone to charity. I am completely stunned by this and actually feel quite sick about it. Ex never provided for the dc, which his dad knew, though I assume ex would have spun him some shit as well, but he would have known ex never provided as he never has money. And fil got on well with the dc and saw them regularly.

I know it's nothing to do with me and didn't happen anyway, but aibu to feel this was a horrid thing to do? I just can't stop thinking about it.

Why is it understandable from fil pov? Why would you feel as fil that your ex DIL benefitting is so bad that you would rather cut your gc out altogether? A DIL you had a decent relationship with when she was married to your feckless ds.
What sort of fucked up person would rather see their gc struggle than run the risk of the OP benefitting?

I find this question really obtuse. How could it not benefit the OP? Whatever it is spent on is money the OP doesn’t have to spend. Driving lessons/ Uni fees/ deposit on flat. I know it’s not necessary to give Dc these things but most parents do , if they can afford it, as we want them to do well in life.