What's the purpose to have him say it? He is n android and thus can't be tested by the force so I see no need. Obviously he is claiming innocence even though I am sure he is not. He admitted to throwing the mine into communications. He can claim he was framed all he wants but I believe that it was an issue with his CPU, but that it was merely an issue of him accidentally admitting it, not some hacking.
Yes, I, a Dark Trooper Mk II, a sophisticated killing machine manufactured to serve the Empire had a glutch that caused me to shout out in a monotone voice that I am tge guilty party. That is believable. And attacks on Stormtroopers have been happening since I've been confined. Clearly I'M the rebel.