Yeah, I don't know. Plot holes ahoy on both counts, I guess. But Eleventy with a baby is too adorable for words, so I don't care as much as I should about the plot holes, and anyway DW has a history of trying to paper over plot holes with entertaining things, rather than actually fixing the problems. *pats show fondly*

Oh, and I'm guessing the reason he knows he has to die is he has perhaps worked out how old he is when he's killed? Although I don't know how he'd know that, as it was the date rather than his age that he saw.