I think the mystery is solved. There is another message on the recruiting board that appears to be from a team member who is not the team leader. However, I happen to know that the team member concerned did start his own team at one point and that he did try to recruit members via the recruiting board - but when that didn't work out, he joined another team and it now looks as though he's posted a message for his second team whereas in fact he didn't, when he posted that message he was still leader of his own team. (The irony here is that it looks as though the newbie member has bypassed the team leader ... who happens to be Terry!)
What the system has done is change the name of the team in the right hand column to reflect the current team of the person posting. If a team leader leaves or disbands their team and then joins another team as an "ordinary" member the message stays the same but the team name in the right hand column changes. This also affects teams where the leader posts a recruitment message and then the team changes its name (there are two messages like that on the board at present).
I think the initial confusion with the two messages for Iva9Brain's team arose because neither message mentioned a team name (unless "Whoot! Whoot!" was a team name) and they were both fairly innocuous "join my team" messages so when the members switched teams and the system changed their current team automatically, it looked as though they were recruiting for their new team even though at the time they posted they weren't.
So in a way everyone is right. It did look as though two non-leaders had slipped through to post messages promoting Iva9Brain's team so she was right to query it, the system does however only allow team leaders to post recruitment messages so gtho4 was rightly rejected when he tried to test the system, and Wesley was also right - if posts are made when someone is a team leader and then they go elsewhere, the system will allow the message but then change the team name on the right.
All of which leads me to conclude that no one was doing anything malicious or intentionally deceitful, nor was anyone trying to bypass a team leader. Instead we have two players who when they were team leaders posted recruitment messages for their teams, weeks or months apart, and when that didn't work out they left or disbanded those teams and joined another. It only looked odd because they both joined the same team which is just a coincidence.
_________________________
The Hubble Telescope has just picked up a sound from a fraction of a second before the Big Bang. The sound was "Uh oh".