Im not sure how you would get around the error, but I noticed that the weapons and all the items are called through dayz_weapons.pbo\config.cpp so.. What happens is the epoch mod dayz_weapons.pbo overrides the origins version, not allowing for any items to spawn/being able to spawn anything. Now unless you can somehow get the origins mod dayz_weapons.pbo to be the one that overrides you will be able to spawn the items. However it would cause a lot of problems because I am pretty sure it also calls the dayz_code.pbo over epochs so most of the stuff is screwed.. Not sure you could go about it