I’ll add something to what I already said:
Children whose parents are really engaged in their church through volunteerism and other ministries, like lector, EMHC, ushers, etc. have a better chance of understanding that it’s important to YOU, so it should be important to them. They are not “bored”. They need to learn all the truths of the faith, but then they need to see
you live it out…through some work of your own, like a weekday Mass once in a while, or going to Adoration, the Rosary group, etc.
Make no mistake…when you attend these other churches, they will corner you right away and want to sign you up for everything and anything, including finding out how much you can tithe. You can’t just go, be entertained, feel good about yourself and leave.
Consider what the Catholic Faith offers

.
In short, start over. It can be done, you just need to make it a priority. If you child had an opportunity on an elite team, you’d rearrange your schedule to make it happen.
We all should do this for God. He blesses us, He gave us His very self in the Eucharist…as a dear priest friend said once, “People should be busting the doors down to get in here. Jesus is here! Where are the thousands?”
Something to think about.
I wish you all the best…Thank you for caring so much about the spirituality of your children. It is NEVER too late with God.
Peace.