..... In the meanwhile I was hoping to see an approximate location.....
I did some digging around and it seems there are more sightings of white leafed Helleborines.
http://www.first-nature.com/fl...
I was wondering if the lack of Chlorophyll is simply the result of an abundance of the proper Orchid mycorrhiza in this particular spot? In that case the seeds would again yield the normal green form.
https://en.m.wikipedia.org/wik...
Or, if you see purple flowers, you may have Epipactis viridiflora? (Reading the Wikipedia link) At least then the plant should come back next year again white. Regarding seeds also keeping this trait - you have the "normal" form nearby, so I would expect a mix of seedlings.
So much for speculations on my part.
You might find this recent thread interesting.
The thread "Variegated Epipactis helleborine." in
Orchids forum