Tell your girl to check out the dive centres on Koh Rong. You know, with the internet. There is one place that's supposed to be a bit shady if I remember, but it's all on the net and will be more up to date than anything I can tell you.
A friend went out diving from KR last year and said it was fine, but I can't remember who with, sorry, not much help. They do overnight trips which might be what you are looking for. Tell your daughter to check out dives heading out from Koh Rong and she'll work it out.
After all, what could ko wrong ? ( sorry, couldn't resist)
But it's true that there was a fatal accident off a dive boat in Koh Rong recently. Worth checking that out too.
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