Are you even organized? Because this doesn't matter, you're not forced to become an atheist when you join a ML party and no one cares as long as you don't break democratic centralism and don't act like a reactionary. A lot of Marxists in South America and in the middle east are religious, no one gives a shit. You can also disagree with Marx and Engels on certain issues and still be a Marxist because, ironically, it's not a religion and Marx is not a prophet. Demanding this level of ideological purity from other people is silly and I'm not convinced it doesn't come from a western-centric and Islamophobic worldview, since you're basically dismissing a huge portion of comrades from the global periphery.

Edit: To add to this, I guess you also think Malcom X, all the liberation theology people and a huge portion of Cuba are "tailists", even though they probably have done more for the socialist than you have. I'm not religious either and I don't believe in god, but you're not going to win the hearts of the people by being a reddit atheist.