That is really strange. That model (satchel radio) and that specific link is not being used at all, nor referenced in any file. Don't tell me its one of those hidden hardcoded things… The only models being replaced is p,v and w_satchel.mdl through a global replacement file. as are all other custom models used.
Satchel in second map is being called inside weaponboxes, player equips, and as loot inside a breakable.
EDIT: Also, during the test before release this didn't happen at all.
EDIT2: Seems that this is a new game bug :), the game looks for a replacement even though no replacement is being referenced, and it doesn't even load the default model. I reported it, let's hope it gets fixed.