Wanting my step kids to bond with my family

I have 3 step sons and I have wanted them to bond with my family but my husband makes it a little difficult. My husband has religious trauma so he has firm boundaries with his son's. They don't go to church and one of his biggest boundaries is none of his son's are allowed alone with a priest or any clergy members. I honestly think any adult and child who isn't the child's family being completely alone together can be an issue. I used to work at a day camp and we were always told to never be alone with a singular child. But my husband is very specific about it being priest. And I respect his boundaries. The problem is most of my family is Catholic and they invite us to a lot of church events. My husband says I can go but he nor his son's will be going. Recently my sister said the church is having a lock in and her kids are going and invited my step kids. Problem is it crosses all my husband's boundaries. Mainly because the priest is putting on the lock in. I asked him and he said no. I said it couldn't hurt to let them go this one time and have fun. So he shoved me an article where a priest has molested young boys around 16 at a church sleepover and my husband said "I'm sure they thought it would be fun too." Then brought up his own trauma and I just let it go. I just really want my step sons to bond with my family. My husband is just so overprotective and has his own trauma. I just want our family to blend well