The thing that makes the most sense is that Charlie was pushing against his masters to much and so he was silenced. Erika was part n parcel of it as evidenced by her actions after the fact. Its well known jews don't give a shit about their own if it benefits them or the whole, this includes children.

Charlie sucked the jew schnitzel and caught the load in his neck when they were finished with him.

How he was killed and, to a smaller degree, who did it are irrelevant with this understanding. Tyler was the fall guy. Even IF tyler did do it it, once again, doesn't matter. The levers were ultimately pulled by the same people.