Peace be with you srobert,
What an awesome task you have taken on. My respect and regards to you on this. Many prayers are coming your way to help you in this! If I can be of some help, please ask be glad to do what I can.
I know many “fallen” Catholics and non-denominational folks. My sister, her husband, and their children went to one in Florida for a time. They attained regularly and did what they could in the Church. At the time they had filed bankruptcy and had little of anything.
The “Elders” of the Church came to them and said if they could not tithe more often and more then they had to ask them to leave the Church. Now that’s not too Christian to me.
I have heard similar stories from others as well. But most returning Catholics I know that attended a non-denominational Church said they left because they didn’t want to be confined (told what to do) by the Catechism and the Canon. No did they think they needed a formal worship service such as Mass. They wanted to worship their own way.
Not all return to the Church, but after a time those that did return felt something was missing. When I ask them what that was they say God was missing from their worship and from their lives. So I think it’s a grass is always greener thing.
Give it time and continue to set the example and I believe they will return to the Church. Never lose touch or faith!