Haven't tried logging in-game with it, just through the site. The account doesn't get recognized, yet I'm like 95% sure I still remember the correct account info.

Managed to log in with another account though, 'only' took 4 hours.
That was an old, silk-free, sub account I had, which leads me to believe if that one is still around the other one must be too. But... It asked me to input a security code after login was succesful, which was sent to my email...

Won't bother asking my friend for that. Especially since everything was gone on the account I managed to log on with. No items/gold in inventory/storage whatsoever, but I still had all my SP and skills. If that's part of the merge it definitely sucks big time... And it means there's no use bothering to log into other accounts.
(Weird part though, it showed I last logged in on the character about a year ago, which is most definitely not the case, so maybe a hack? Seems improbable unless it was an exploit on Joymax's side.)

EDIT: Did manage to log on my main account after all as well. Still have a few select items, but most of it is gone. Warlock rod, shield & chest are gone, but other items are still equipped. No gold left in inventory. Nothing in storage except for a bit of gold. Untradeable items, like avatar dresses, are all gone too...