No Worries Mate
I've sunk plenty of those 4 stackers in the Med, 3 in the same career and 2 in one patrol even, in addition to other passenger liners, That Kaleun would definitely have been tried for war crimes if he had survived

a total of 8 passenger liners sunk in one career lasting 8 months is bad for one's reputation
those misses are also a good lesson about getting careless with new technology