Having installed, run, updated and maintained several forums over the years, it's a fairly simply process preventing spam. Running any community forum requires rules, admins and moderators! Something that Obihai appear to be lacking.
All modern forum software contain features that help prevent spam and spam bots as standard. As we all know already, Obihai are running an old version of Simple Machines and no doubt, like most companies refuse to spend any time (or money) upgrading.
It is however very concerning that Obihai don't appear to have any staff available to remove offensive spam!
Also worth noting, companies usually require an NDA agreement or similar in place before allowing someone access to moderator/administrative privileges. Had to sign a few myself in the past!