First of all, amych, I'm really sorry. That totally sucks, and when I look for IT stuff for Dan, I'll pass anything I find to you, if it looks up your alley.
Second, kids on the internet. Micah is almost 13 and had been on Instagram for about a year and a half. We have his password, and I'm friends with him on Instagram, so if I see anything hinky, I'd be on him like stink on shit.
Wattpad -- hmm. I think I've told y'all the story about how I was reading a heaving bosoms bodice ripper in 6th grade after all my work was done, and my teacher marched me to the office to call my parents about my "inappropriate reading material" and got my dad on one of his every-5-years sick days.
He listened, asked if I was done with my work, was told I was. Asked if I was causing any trouble or disturbance, was told I wasn't. Asked how my grades were, was told I had straight A's.
And then he told the teacher that he and my mom were the parents and unless there was some kind of written school policy about books, that I could read whatever the hell I wanted during free time and politely said good-bye.
When I got home, he had been looking over my mom's collection of romances and had picked out the one with the most lurid cover and told me to take that one to school tomorrow, and it I had any free time, to take it out and read it.
BUT -- I was a freaky mature reader. I was reading really adult books at about six -- I asked my parents what "rape" was when I read a historical novel about Sacajawea 1500 pages long when I was 6, and that's when my parent's understood how freaky my reading brain was. They got me a dictionary, and asked me to ask them to explain anything I didn't understand to them. They got me a 10 volume set of human sexuality books aimed at teenagers when I was about 8 (I think so they wouldn't have to explain cunnilingus or fellatio EVER.)
So...I think the advice you've gotten is pretty spot-on. I'd say have a joint account with her, and make sure you check the history (and if she ever erase the queue, he privileges are gone.) It depends on her level of mental development.
I was a socially awkward kid and teen because I lived in books so much that I was kind of alien to other kids, BUT I grew up to have a genuine love of knowledge and an empathy and tolerance for all kinds of cultures and mores. I think if I'd had the internet as a kid, I would have connected with more kids like me and not felt like such an anomaly.
But, hey, when Micah gets a phone and/or social media sites, I have great comfort in knowing my husband is a mad hacker and we'll be keeping a mad eye on his interactions. And yo, thanks to my parents, he's had a great book on human sexuality I bought him on his shelf for two years. He was totally grossed out by it when I bought, so I have no idea if he's read it...but then, that 10 volume set on human sexuality? I read it in private, too.