This has been covered several times.
Christi, who runs a dive operation in Cozumel, gave a detailed explanation, and she has repeated it a few times, I believe. Yes, you do need a hologram if you get your cert in those locales, but only if you do the whole thing there. If you are a referral from somewhere--like the U.S.--that does not have holograms, they only have to indicate that you are a referral on the form. That's all there is to it.
Unfortunately, some operators apparently skipped the local informational meeting and don't know that. (That exact scenario was discussed in anotehr thread.)
And families can share books.
Christi, who runs a dive operation in Cozumel, gave a detailed explanation, and she has repeated it a few times, I believe. Yes, you do need a hologram if you get your cert in those locales, but only if you do the whole thing there. If you are a referral from somewhere--like the U.S.--that does not have holograms, they only have to indicate that you are a referral on the form. That's all there is to it.
Unfortunately, some operators apparently skipped the local informational meeting and don't know that. (That exact scenario was discussed in anotehr thread.)
And families can share books.