The photos tell me that the connecting rod bushing (where it mates with the crank shaft) failed, creating play between the crank shaft pin and the connecting rod. This play allowed the connecting rod to come into contact with the engine case causing the rest of the damage.

Over-revving did not cause the problem, a bad bushing did (no sign of stretching or hole elongation I could see in the photos). I would contact tower hobbies regarding a manufacturing defect that led to the engine failure (always being polite and provide the photos as evidence). Worst case, they do nothing. Best case is they provide you with an engine swap.