Going to try to keep this brief, but feel free to ask me to elaborate on anything.
Firstly, regarding the alleged metagaming, from my end there was no OOC bias. There were several IC reasons to be suspicious which I will get in to.
Ricky's summary of the round's events matches what I remember. While Eva was dealing with the power sink, Clark was dealing with the bug in the consular's office. In the course of the investigation, it was found in PDA messages that the janitor was paid/extorted to put the bug there. While all this was being worked through in the brig, Johnson was nowhere to be found which was the first (minor) point of suspicion.
The round got a lot more chaotic around this point, especially over sec's radio, so I might not have the order of events 100%. HoS ordered Johnson detained and searched. Johnson did not readily cooperate so the officers started to baton him. When he went down he dropped the hardsuit, that and him moderately resisting are 2 other IC reasons we were suspicious of him. If someone turned it into the lobby and Johnson did just happen to pick it up right before he got detained, very unfortunate timing for him because it made him look very guilty.
Around the same time we found the PDA messages between Johnson and Sarrj. Nothing incriminating in the messages, but given how similar it was to the messages between Sarrj and the janitor which were used to plan the bugging of the consular's office and the prints/fibers suggesting that they did physically meet, this was another red flag.
Towards the end of the shift the HoS asked Clark and Eva whether or not Johnson should be let go. With the aforementioned reasons to distrust Johnson, I think there was ample IC probable cause to want him to stay detained while the rest of his case was worked out. Unfortunately, due to the round ending and the numerous other things going on during the round, there was never really enough time to properly investigate Johnson.
Happy to expand further on anything, but that's about the gist of it.