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I'd say the general sentiment in the spirit of Parting-Words Regret, especially if the character has serious doubts about ever getting the chance to apologize (they genuinely believe they'll be executed soon or otherwise never escape or that the counterparty will be missing forever).
As for the situation itself of two parties away from each other echoing the same sentiment, I'm finding things like Twisted Echo Cut, but no plain and simple Echo Cut. Not sure.
So, there's a scene in a movie I was watching where a character (a teen boy who's been captured by the villain) regrets that he never had a chance to apologize to his uncle (whom he had a spat with at the movie's beginning, before the plot kicked into gear)- and then the scene cuts to the uncle, who is worried about his missing nephew and lamenting that he was too hard on him.
It feels like a trope is in play here, but I can't seem to find anything specific...