My Wife told me she had gone on MissingMoney.com out of curiosity and saw a few items that my Father was connected to. He passed a few years ago.
My immediate response to Her was FORGET IT!
I thought before I completely blow it off I should ask if this is legit or as I expect, a way to scam money or info from me.

Has anyone had experience with this organization?

File the claim directly with the state in question. Do not go through any 3rd party service that charges a fee. State escheated funds are a real thing.

Yep. Every state I've lived in has a (free) state government website for unclaimed funds.

Don't bother with a third party service, especially one that wants money for it.

And be prepared to jump through some hoops if you are trying to claim funds for a deceased relative.

Here's the online search for unclaimed funds in your neck of the woods.

Several years ago, I went state by state for all of the places I lived. For each state, I used the official state government website and:

found some money owed from my insurance carrier from my AK days. Enough to buy ammo and go shoot at the range for an hour.

found some money for my Dad

found some money for my paternal uncle

Checked again this morning and didn't find anything.

As I understand it Missing Money can tell you if there is money somewhere and then it's up to you to know where it might be and go direct.
Most people can figure it out from there.

I found some life insurance money owed to my niece from my late brother. I sent her the info and she said it was such a nightmare trying to get it she finally gave up. She said it just wasn't worth the effort. Hey, at least I tried.