This seems like this person really likes your story and wants to write her own version of it as a sequel. It's unfortunate that you can't find him or her except for on that Wiki.
Whatever the case, if and once the story is uploaded onto Fanfiction.net, you need to take action immediately.
Two things:
1) I have more accounts than just fanfiction wiki: I'm at ice age wiki, lbt wiki, fanfiction wiki, rio wiki, the ice age wiki, ice age fanon wiki, ice age franchise wiki, happy feet wiki, carnosaur wiki, jurassic park wiki, jeepers creepers wiki, tremors wiki and the final destination wiki
2) I never had an account for fanfiction.net, and if I did post fanfictions there, they'd be ice age fanfictions, plus my
validated account wasn't working right.
Also, Serris, if you were wondering why I wrote an unofficial sequel, it because I was new at righting fanfictions, so I started with something I knew very well. But that won't happen again, I sticking with writing my own fanfictions, rarely LBT. Only LBT fanfiction I'm working on is my temperarily cancelled fanfic The Land Before Time/Ice Age crossover and help right with fanfictions that are going slow by request, so if anyone wants to have me help with writing fanfictions, contact me. I have nothing to due, and I've ran short on ideas with Ice Age fanfictions. I just finished three! Two yesterday, and one today, but I have tons of ideads for war-fics I've read, heads up.