Wondering Where People Are Now

This girl I know from university we share a mutual friend whom I will call J. I met J during my second year of university and I would see him at the dining hall (he was there only for the fall semester before deciding to cook for himself as he lived in the apartment style residence and I still was living in the dormitory style residence) and at fencing club (I at this point have been fencing for a year while he just started out). It was through him I came into contact with the girl whom I will call N. N has asked me a couple of times if I have heard from J since she, from my perspective, developed a close friendship with him (she has a boyfriend at this time and I'm not sure if she it still with her boyfriend). Last time I think we both heard from him was some time during my third year in the winter semester (early 2010). N had already graduated from university back in 2009 and was studying somewhere in South America. Many months later (maybe it might've been earlier this year) she asked me if I have heard from J. I haven't but I have theories of what might have happened to him/where he might be.

So here's J's background: He's around my age being born many months before me but started university a year after I did. He comes from British Columbia, Canada and later in life settled in Alberta (specifically Fort McMurray and he also worked there too). He grew up in a Pentecostal family but many months before we met he became an atheist but he still has a little struggle with his religious beliefs (most of the part he said he was atheist). He was studying biology at the same university I am currently attending but he came close to changing universities for a better program. He eventually stayed as I moved into the apartment above his in my third year. We didn't see much of each other even though we were neighbours and the last time I saw him was before exams for that fall semester started. I didn't see him after that and the reason he didn't come back because according to what he said on facebook he was ill over the break, more or less shortly before going back for the winter semester. When I spoke to him he told me he had an ulcer. I suspected that he wasn't going to come back as he was the apartment's environmental officer and recycling started to pile up under the stairs. Some time later his facebook activity became low to the point where I was unfriended and then his account disappeared. I know his account was deleted as N hasn't heard anything from him.

Now for the theories:

1. J had some sort of epiphany: I mentioned that he became atheist but had a small struggle with his religious beliefs. Chances are he became ultra-religious and decides that social networks are of the devil but his family members still exist on there so I don't think this is the case. He may not have had a religious epiphany but maybe something that might make him decide to unplug from social networks.
2. J probably doesn't have any use for facebook: facebook was my main way of contacting him. N I believed also had his phone number and mailing address on hand. I also think that she told me she sent something to him but hasn't heard back so this theory, therefore, is bogus.
3. Moved away to start a new life: probably doesn't want anyone to find him
4. This one I hope is not true but it could be possible that he's dead. I do not want to believe this one as some people whom I know are dead still have facebook pages in tact, unless he planned this. Again I do not like this theory, I hope it's not true but it still counts as a possibility.

Hopefully I do run into J some day. Just the thought of knowing that he's alive and doing well will satisfy me enough.