It’s impossible to pick up the lame man in this mystery. I read more people had this problem, but that it should be resolved a long time ago. But it isn’t.
I first brought the blind man to the spring.
then I loaded a saved game and went to the lame man first. But this didn’t help.
I play it on the PS4 and have installed patch 7.20.
In general I experience lots of bugs and glitches in this game, but most of the times restarting or lading a saved game helpt. But not in this case.