Even Russell couldn't say for sure whether the Church's ideology was good or bad;
even he, in his current state, couldn't forcefully and rightly declare, "This is absolutely wrong, sinful."
Because indeed, they held no selfish intentions or desires.
Every struggle carried out just to "survive" is beyond good and evil—it's a different kind of choice that transcends moral concepts, a choice about life and death.
Of course, some people can offer everything, including their lives, for something greater than themselves. Yet, others may only wish to survive, willing to pay any price just for continuance… but that doesn't mean the latter is wrong, nor can one demand others to sacrifice themselves for the "greater good."
The Church was under no obligation to believe in Russell. Even if the path they followed was the worst possible option, it was still a path that could be taken. A narrow path is always better than a dead end.
—The so-called "Great Fusion."