Bots leave at end of map, Same as title Options

[snibborsrealm]

I am running a hl2dm server. I have no problems getting the bots to join a game once I enter the cmd in my game console but they dont join before that or re-join at the start of the next map.

Here is my commands in my autoexec.cfg.

bot_chatter off
bot_add
bot_quota 3
bot_quota_match 1
bot_quota_mode fill
bot_join_after_player 0
bot_difficulty 2
//bot_prefix ""
bot_defer_to_human 1
bot_auto_vacate 0
bot_chatter minimal
bot_allow_grenades 1
bot_allow_pistols 1
bot_allow_rifles 1
bot_allow_rogues 1
bot_allow_shotguns 1
bot_allow_snipers 1
bot_allow_machine_guns 1
bot_allow_sub_machine_guns 1
bot_allow_shield 1

What else should I do and if there a cmd I can use to add bots from my server console?