HLDM: Host crashes with Host_Error: PF_precache_model_I when loading "mario_sewer"

[nixRidge]

When loading the map "mario_sewer" with RCBot, the server crashes with the following message:

FATAL ERROR (shutting down): Host_Error: PF_precache_model_I: 'models/w_chainammo.mdl' Precache can only be done in spawn functions

Full log

./hlds_run +maxplayers 16 +map mario_sewer +ip 192.168.0.51 +sv_lan 1 +port 30000
Auto-restarting the server on crash

Console initialized.
Using breakpad crash handler
Setting breakpad minidump AppID = 70
Forcing breakpad minidump interfaces to load
Looking up breakpad interfaces from steamclient
Calling BreakpadMiniDumpSystemInit
12/14 21:15:59 Init: Installing breakpad exception handler for appid(70)/version(8684)/tid(197067)
Protocol version 48
Exe version 1.1.2.2/Stdio (valve)
Exe build: 19:52:19 Aug  3 2020 (8684)
STEAM Auth Server
Server IP address 192.168.0.51:30000

   Metamod version 1.21p38 Copyright (c) 2001-2013 Will Day
     Patch: Metamod-P (mm-p) v38 Copyright (c) 2004-2018 Jussi Kivilinna
   Metamod comes with ABSOLUTELY NO WARRANTY; for details type `meta gpl'.
   This is free software, and you are welcome to redistribute it
   under certain conditions; type `meta gpl' for details.

RCBot: plugin attaching
[RCBOT] Reading Bot Folder
[RCBOT] Bot Folder File not found! using default (half-life/rcbot)
[RCBOT] Added: name="", pass=*, accesslev=63, steamid=STEAM_ID_LAN
[RCBOT] Added: name="Ridge", pass=Lunatea, accesslev=63, steamid=STEAM_0:0:19112330
[RCBOT] 2 users added to list of RCBot users
[RCBOT] commanding is now 0
[RCBOT] wait_for_orders is now 0
[RCBOT] dont_shoot is now 0
[RCBOT] chatting is now 0
[RCBOT] real_mode is now 0
[RCBOT] max_bots set to 4
[RCBOT] min_bots set to 0
[RCBOT] gorge_amount set to 0.3
[RCBOT] update_ladder_time set to 0.0
[RCBOT] tooltips is now 0
[RCBOT] max_path_revs set to 150
[RCBOT] max_update_vision_revs set to 200
[RCBOT] update_vision_time set to 0.03
[RCBOT] reserve_bot_slots is now 0
[RCBOT] chat_percent set to 0
[RCBOT] chat_reply_percent set to 0
[RCBOT] chat_dont_learn is now 1
[RCBOT] balance_teams is now 0
[RCBOT] chat_reply_to_bots is now 0
[RCBOT] allow_botcam is now 0
[RCBOT] disable_weapon_learning is now 0
[RCBOT] disable_bot_squads is now 1
[RCBOT] ts_dont_steal_weapons is now 0
[RCBOT] ts_dont_pickup_weapons is now 0
[RCBOT] ts_kungfu is now 0
[RCBOT] marine_auto_build is now 0
[RCBOT] RCBOT BUILD Aug 24 2024-23:36:12
[RCBOT] Reading Bot Folder
[RCBOT] Bot Folder File not found! using default (half-life/rcbot)
[RCBOT] Added: name="", pass=*, accesslev=63, steamid=STEAM_ID_LAN
[RCBOT] Added: name="Ridge", pass=Lunatea, accesslev=63, steamid=STEAM_0:0:19112330
[RCBOT] 2 users added to list of RCBot users
[RCBOT] commanding is now 0
[RCBOT] wait_for_orders is now 0
[RCBOT] dont_shoot is now 0
[RCBOT] chatting is now 0
[RCBOT] real_mode is now 0
[RCBOT] max_bots set to 4
[RCBOT] min_bots set to 0
[RCBOT] gorge_amount set to 0.3
[RCBOT] update_ladder_time set to 0.0
[RCBOT] tooltips is now 0
[RCBOT] max_path_revs set to 150
[RCBOT] max_update_vision_revs set to 200
[RCBOT] update_vision_time set to 0.03
[RCBOT] reserve_bot_slots is now 0
[RCBOT] chat_percent set to 0
[RCBOT] chat_reply_percent set to 0
[RCBOT] chat_dont_learn is now 1
[RCBOT] balance_teams is now 0
[RCBOT] chat_reply_to_bots is now 0
[RCBOT] allow_botcam is now 0
[RCBOT] disable_weapon_learning is now 0
[RCBOT] disable_bot_squads is now 1
[RCBOT] ts_dont_steal_weapons is now 0
[RCBOT] ts_dont_pickup_weapons is now 0
[RCBOT] ts_kungfu is now 0
[RCBOT] marine_auto_build is now 0
[RCBOT] RCBOT BUILD Aug 24 2024-23:36:12
[RCBOT] No map specific config file found (rcbot/map_configs/valve/mario_sewer.cfg)
loading waypoint file: rcbot/waypoints/valve/mario_sewer.rcw
[RCBOT] Waypoint file rcbot/waypoints/valve/mario_sewer.wpt does not exist!

[S_API FAIL] SteamAPI_Init() failed; SteamAPI_IsSteamRunning() failed.
CAppInfoCacheReadFromDiskThread took 5 milliseconds to initialize
Looking up breakpad interfaces from steamclient
Calling BreakpadMiniDumpSystemInit

couldn't exec listip.cfg
   VAC secure mode disabled.
[RCBOT] Adding Bot...
[RCBOT] HAL : restoring brain to [BOT] Jumping Flash

Host_Error: PF_precache_model_I: 'models/w_chainammo.mdl' Precache can only be done in spawn functions
[RCBOT] [BOT] Jumping Flash Message : BUG: Could not find [BOT] Jumping Flash in list of clients, may be caused by a player that hasn't connected properly Report bugs to : Cheeseh (cheeseh@bots-united.com)
Dropped [BOT] Jumping Flash from server
Reason:  Server shutting down
FATAL ERROR (shutting down): Host_Error: PF_precache_model_I: 'models/w_chainammo.mdl' Precache can only be done in spawn functions

Loading the map without RCBot works fine.

Using the following software:
HLDS Linux legacy branch
Metamod-P 1.21p38
RCBot v1.51-beta9

Have also tried reHLDS with Metamod-R to no avail.

Map link: https://gamebanana.com/mods/59813

Workaround:
This AMX Mod X plugin lets me precache said file, and allows the map to be played with RCBots:
https://forums.alliedmods.net/showthread.php?p=583443