Ok, so DH spoke to DSS this evening. DSS cannot see anything strange about the situation.
DH was trying to get to the bottom of the Sainsbo's carpark bit and who suggested that but he just said 'it was mutual'. Obviously that's not how ideas happen, so haven't got to the bottom of that.
But, he did tell DH the girl's name, so I've been looking at her facebook and it does look sort of ok. There is a girl with the name he gave, who lives in the town that he is going to, who is 17, so the age is correct. There are quite a few pictures and some interactions with friends (not many though) Her fb goes back to 2009 which is quite reassuring. It's not a very active page, but she may just not be that popular?
She is friends with people of the same surname who have much more active fb pages, so I think she is real, but maybe not that popular.... hence why she might think this venture is a good idea (and maybe why her parents are supportive.)
Sorry I know I'm being a massive stalker - it's not so much him having a terrible time I'm worried about but him coming to harm. If he goes and it's just really awkward well, it's not like everyone didn't tell him it was a bad idea. So the only think I'm really worried about is that it's someone who would hurt him.
Apparently, although the parents are picking him up,she is giving him money for the coach back? Do you think the parents picking him up is them being cautious? DH has said that if he persists with this idea he will take him there instead of him being picked up (hasn't suggested that to DSS yet) and obviously we would give DSS money so he isn't relying on that.
DSS also said to DH that he didn't want to ask her to change the plan now because she might change her mind about wanting to meet him.