Oh! Heh...well, I figured "Owner is seized" (under External) covered that.
No those are two completely different risks.
Seizure of the owner would be effected by some government to stop the operation of SatoshiDICE.
Secret leakage would be effected by some non-governmental entity to continue operating SatoshiDICE in a completely predictable manner.
Libertarians (like Erik) are particularly easy target for the later kind of the risk.