Stone cold terrified, but still horny

Back in the 1980s, my wife and I - both sexually inexperienced - decided to join a nudist club. We thought it would be exciting and liberating but, as it turned out, the naturists we met really were the most sexless people we'd ever met. With one rather marked exception...
At the end of our first nervous and rather disappointing day as naturists, we were invited to the home of James and Laura, the couple who had seen us through our first day of semi-public nakedness. A bit older than us perhaps, but friendly and welcoming, we accepted, more out of politeness than enthusiasm.
Their home was large, pleasant and comfortable and when we arrived there, without the slightest hesitation, they got undressed. Well they would, of course; they were committed naturists, weren’t they? No shame, no self-consciousness. They were clearly very comfortable in their own skin and were enjoying being naked in their own surroundings. They invited us to get naked too and we did, but with rather more awkwardness than our hosts.
As we drank wine together, talked about our first day at the club and moved around the house and their large, private garden, it was clear that they were taking pleasure in us looking at their bodies. They were talking freely about naturism and the pleasure of being naked with others and as the evening went on it seemed to us that they were getting closer and just a little more intimate with each other. At one point they emerged from the kitchen together. James had the beginnings of an impressive erection. Without any hesitation he asked us if we liked what we saw, and invited us to touch them both if we’d like to.
A movie of this situation would have us all piling into a raucous foursome, but that’s not how it worked out. Nervousness and inexperience meant that frankly, we were stone cold terrified. We made a lame excuse about one of us having a headache and hastily got dressed and left.
It could have been spectacular. Perhaps it could still be? Thank you!