And I guess I should answer the question from an Alpha perspective (I'm sure someone else will answer for APO
For Alpha....after reviewing the documents on the public portion of the website, it SEEMS like the initiation is concurrent with the granting of the provisional charter. But it clearly states that chapters are provisional for the first two years. Permanent charters are automatic after two years unless something is amiss. If the provisional charter fails, then the remaining college students are considered members of the sponsoring alumni chapter.
So basically, if it fails, they're still members.