Give 'em a couple days - developing country, other side of the world, etc. Occasionally a few days would go by before I got a reply from them, but most times I got a response within 24 hours. Your trip is still 11 months out, right? I think you have plenty of time (I know, you're itching to get things nailed down, negotiations with the spouse, etc....but remember, Island Time....).
Yes, my report above was for OH III. Was on it 2 weeks ago (now seems very far away...).
If that doesn't work out, there
MAY be another alternative worth considering:
Palau Siren. This may be a little tricky, though. That boat looks (well, looked) spectacular, and was probably my first choice as I started long-range planning (I plan things like this 1-2 years in advance). But apparently the boat "sunk" or was "wrecked" (depending on the reports and your definition of the terms) about a year ago. But that boat is afloat again - I saw it 2 weeks ago, moored in Koror harbor. I asked the crew of our boat about it - I thought it was sitting on the bottom somewhere. Apparently, it ended up on a reef, but not (completely?) underwater, they re-floated it, and according to the OH III guys, they were working it again (although it was in the harbor when we went by, and we did not see it out on/near any of the dive sites).
IF it's still in nice shape (a big IF), I'd give it a good look - it sounds lovely. Before I committed I'd want to read reports from someone who has been on it after its "sinking" and (presumed) refurbishment, but....if they fixed it up "good as new" it might be a very sweet boat.
Hope some of that's helpful. Good luck!