[KWo]

Can You just try these tests:
1. No mean and no AMX (or AMX MOD X - which one and what version are You using?) - then kick some bot by pb remove #bots_id (or bots_name) instruction and add some bots by pb addbot - to see if it woks correctly.
2. podbot mm R2B46d and AMX (AMX MOD X - this one You really have) only - and the same - remove some of them, then add few and look if they spectate or not.
3. podbot mm R2B46d and mean (without AMX or AMX MOD X) - to be sure which one makes us troubles when You are adding some bots (remove and add some of them).
4. then everything together, but podbot mm at the end of the plugins.ini and the same test (I recommend personally to have podbot mm always at the end of the plugins.ini)