I've also been trying to delete my account, but I don't have the relevant option as shown here
You can not. In the past, theymos changed username to Anonymous but he did not want to do it for a long time ago. See the quoted posts and related topics, to know your chance is zero.
As you can see here, I only change the username to "Anonymous" on request.
I'd like theymos' statement on this rather than speculations.
Judging by other threads here, and looking at the help section, it should be technically possible. Heck over at Litecointalk you can do it yourself, and it looks like the same forum software.
He's said before he doesn't do it anymore.
It's not possible. Just abandon it.
Even if your account fortunately to be deleted, data is still available on the Internet with
Loyce.clubNinjastic.spaceand the internal database of the forum.
Did you use your real account to PM theymos? Did you get that message when you sent a PM to theymos with your newbie account?