The CRA doesn't use the word "and". It's "or".

manifesting, promoting, sustaining, or increasing belief

Meaning it's optional. Also, "promoting" is quite vague. TST doesn't qualify in any case, though, because what are they "manifesting, promoting, sustaining, or increasing belief" of?

a religion’s three key attributes, which are: faith in a higher unseen power such as a God, Supreme Being, or Entity; worship or reverence; and a particular and comprehensive system of doctrines and observances

So yeah. Non-theistic Satanism doesn't apply. We have reverence, we have doctrines and observances...we do not have a Supreme anything.

TST primarily operates in the USA, so the IRS code is much more relevant. Let's see which part of this applies:

advancement of religion

That's it? "Advancement" is even more vague than "promoting"! I can do a lot of things that "advance" my religion without trying to recruit people. Adding more programs to my congregation, for example. Hey, now we have a book club! Satanism has been advanced.

In fact, I think that most Satanists would say that trying to recruit wouldn't be advancement at all...it would be a big step backwards.