The wife and I have been to Hedo 12 times so far so I can probably answer many of your questions. First of all, Don't rely on rumor or what other people have heard. That's how misinformation happens. People that haven't been there shouldn't be telling what goes on there.
First of all, there is no longer a "Prude" side. It is now clothing optional. You can be naked there if you would like but you don't have to be. You do have to be nude on the nude side. I'm not sure why someone would want to just "watch but not join in" but to each their own. The nude side is like a naked frat party atmosphere just about 24/7. Fun in it's own way but we often need a break from the constant party so we enjoy the quieter clothing optional beach. There are usually several other people there now that it is clothing optional, not just 10 people as previously mentioned.
You won't necessarily be asked to swing, but if you are a simple "No, thank you" should be enough.
If the resort is full, day/night passes are often not available. November -February are the busiest times so I would call before making the trip to the resort and be turned away.
Most of all, Hedo is what you make it. If you want a swinging orgy, it can be that. If you want naked party fun with a bunch of friends, it can be that too. If you just want to be naked on the beach reading a book, It can be that as well.
Most of all.....never listen to what people "heard" goes on there.
Feel free to PM if you have more questions.
Greg