Marines bots are not seing you if you are cloaked and not moving, since the bot code is only checking the "IsFullyCloak" information. However they are quite sensitive to mouvement and also sounds.

Just keep in mind that the bot code currently running in ns2 is only there so we do have good enough bots knowing the very basics like moving, shooting, evolving, or building but that's pretty much it. Rewriting the bot code would take unfortunatly a lot of dev time we don't have (but if you know a bit of lua, and are willing to give it a try, pull requests are of course more than welcome).