well if we needed a smoking gun here it is. Thanks to Sven's mention of Green jacket Auctions - where the Maxwell collection of photos were first sold - I have found another shot of the 10th that looks like it was taken further down the fairway so that the new Maxwell green is now visible, along with its bunkers as well as Mac's old greenside bunker that was retained. The trees at the left of my photo match perfectly with the trees at the right on this one. You can even see the gap between the trees at the far right.
Case closed I think.
Also, Bryan has highlighted the matching treetops, amazing that those pines look so similar after 75 years. Guess they were mature pines then and haven't grown any since.
Been a fun discussion! Thanks everyone.