When people gather at a wedding , baptism , funeral, etc, we all pray together regardless of what particular denomination, also when families gather for holidays, they are rarely all the same, and yet it is common for us to all pray the lords prayer, even people at AA meetings do that.
So do not worry about the church people who insist on this or that, God loves when we pray and he alone is all we should worry about as the Gospel here says.
4“I tell you, my friends, do not be afraid of those who kill the body and after that can do no more. 5But I will show you whom you should fear: Fear him who, after your body has been killed, has authority to throw you into hell. Yes, I tell you, fear him.
◄ Matthew 18:20 ►
For where two or three gather in my name, there am I with them."