Helleborine - not sure which one

Helleborine - not sure which one

Observation - Helleborine - not sure which one. Description: One flower only, found in inner city woodland local nature reserve. Not recorded here before. I though it might be green flowering helleborine but doesn't have the pendulous flowers. Also leaves aren't all parallel so I wondered if it might be a green flo

One flower only, found in inner city woodland local nature reserve. Not recorded here before. I though it might be green flowering helleborine but doesn't have the pendulous flowers. Also leaves aren't all parallel so I wondered if it might be a green flowering form of Epipactus helleborine.
Any thoughts much appreciated.