I'd love to see a pic of a 41 back Dengar, but this is because I'd love to see a picture of a 41 back Dengar, rather than needing to see one to believe it exists. It's been on my wants list for some time and will remain there for the foreseeable future no doubt.
I do appreciate people's desire to have some confirmation. A fun part of collecting is the discovery of new pieces, (the VC Jawa is a good recent example). Some of us have been doing this for decades and new things turn up every now and then which change our understanding slightly, and sometime considerably.
But the end of the day, as much as much as I'd like to see one (not to mention own one) it is up to the owner of any item, in this case Darren, to do with it what they will. If they choose not to show pictures then that is entirely their choice. If they choose to open it, burn the cardback and melt the figure in the microwave....that again is their choice - please don't do that though
No one has any entitlement to anything in this hobby, other than to be treated with respect as a fellow collector. No one has any inherent ownership over anything, unless they directly own it, be it an item, a picture of that item or information about it.
I'm sure no one intended to give anyone any stick regarding this - and it has somewhat distracted us from the original OP's question.