Thanks for the chapter!
Considering he probably didn't know about most of the corruption of the various nobles before he died, how is he finding out about things like the General and his family's repulsive choice of eating the other white meat? Servants talk and hiding that many bodies will get exposed at some point. In any case, why was the mother saying the meat for the next meal had been decided? Using such a strong poison would've tainted whatever they cut off the MC and poisoned whoever ate it as well. Or was she talking about eating the servants digging the holes?
@Goldenzeal More likely the family's behavior, at least the mother and sons if not the father, is a result of both rather than one or the other. Hence, having rotten personalities is due to the father's bad teachings and considering everybody else as a potential meal in addition to whatever ailments and conditions afflict someone from eating too many brains, especially improperly prepared ones. The General still able to act composed could be because while has rotten personality prefers the other parts and rarely eats brains.