I'm going to sound like one of them dang dirty millenials, but that's victim blaming. They definitely weren't lying when they said asking for a picture isn't the same as asking for a kiss. This is classic Chris mentality, something is either 0% or 100%. He probably thinks an invitation for a picture is the same as inviting physical contact.
Even if they did not directly confront Chris, Chris was still expected to respect boundaries generally agreed upon by social norms. That is something expected of adults, it's on Chris to overcome his autism to learn it, not on others to be expecting him to do it and pre-emptively say no. It's not like it's ok to kiss stranger girls until they vocally protest.