I know that you said that you didn't want to cook the offal, but it's an easy thing to do. I use one of those big turkey oil-cooker set ups that I bought at Ace Hardware real cheap at Thanksgiving time. I think I paid $39. It includes a giant pot big
enough for a jumbo turkey, the stand, and the propane regulator & hose. It is setup to use an inline timer which i sometimes bypass depending upon what I'm cooking. All you need to add is a bottle of propane and you're set to cook.
Offal doesn't need much cooking to make it safe to feed back to the hens. In fact, the hens would eat it raw......and they do when one dies in the pen and I overlook the body. Those hens will eat the dead one all up, except for big bones and big feathers, real opportunistic cannibals. But I feel that it's safer to cook the chicken offal before feeding it back. I simply heat
water to boiling, add offal, bring things back to a boil, turn off and allow it to cool. Then feed. All the slaughter waste goes into the cook pot, including heads, feet, feathers, and anything else. The hens will eat just all of it.
I don't see where this is a dangerous practice, considering it is heat treated before feeding.
My ducks (muscovies) eat the same thing that I feed the hens. They appear to do fine on it.