Yes, Latin Pass does have to "verify" every item that doesn't post... that is, they send the documents electronically to the company in question and wait for an answer. Avis is notorious for slow answering, which combined with LP's slow sending in the verifications produces endless delay. I am waiting for one Avis posting, for which I sent the documents in July.
Nevertheless, it gives me hope to see some postings of the bonus reported here. I really enjoyed going for the 500k, enjoyed and was impressed by the airlines. But I can't say I have enjoyed calling for 14 weeks to be told "call again next week" when inquiring about one Avis posting.