I don't think your polarizer is too cheap. I don't have a hoya, but the brand has quite a good reputation and I have never heard that their polarizers wouldn't do the job. The quality of polarizers is rather judged in respect to their coating and optical clarity. The linear polarizer I use was also very cheap and maybe it is not of such a high quality but the effects it produces are very obvious.
WB shouldn't be the problem neither. Polarizers do not (at the first place) influence colors but rather filter the incoming light.
I'm not sure, what the problem was in your case then:?. Maybe the explanation with the marine haze has something to it and it simply wasn't the right time.
If you want to check out the efficacy of your filter, you can try it at home though. Just aim at some reflecting surfaces like plastic, wood or glass (not metal) and turn the polarizer ring. If the Hoya filter works correctly, you should notice obvious changes in the intensity of the reflections.
May I ask you a question in turn? What program do you use to read work those raw files? I tried out "silky pix", which worked quite fine, but it is not freeware. I'm not yet sure if I'm willing to pay the price of around 120 $$ for it. Do you have a cheaper idea?