WHAT REALLY HAPPENED-
Shadowwolf played Slender as normal. He grabbed his few pages and inevitably encountered Slenderman. However, this was one of few anomalies with Slender, as the game did not end. Slenderman himself emerged from the static, and stole Shadowwolf from within his own home. With Shadowwolf lost from the rest of humanity, Slenderman tried to make Wolf's disappearance subtle, so no one would be suspicious.
He swiftly sat down at Shadowwolf's computer, and noticed a task still open:his web browser, with Shadowwolf still logged in to T9k. He recognized this as a forum, and hastily typed out a post filled with gramatical errors, given Slenderman's limited undsrstanding of the English language. This post would surely hide his disappearance. No one would suspect a necromantic post declaring his experience with the game, and that he remained unharmed! With that notion, the monitor faded once again to static, and Slenderman slipped back through to whatever realm he originates from.
He's taken Shadowwolf! The evidence is right there! Look at his previous few posts, properly structured, capitalized, and punctuated! The Shadowwolf we once new no longer is with us, and we have but the occasional poorly-written posts from Slenderman to slowly fade Wolf out of memory!
Rest in peace, Shadowwolf. If you truly can.