I hope you like double-compressed files because I meant to do the edit with the uncompressed WAV files but I used the MP3 I'm too lazy to go back and redo it.

I see Asgore get a lot of flak for everything he's done, and rightly so. But is he really an antagonist or villain? No, of course not. Just like most of the characters in Undertale, Asgore is more of an anti-hero than anything. Truly, he wishes for the freedom of his people, but is afraid that monsters would simply be eradicated by humans if they were to be freed without a proper ambassador, so even though Asgore could have left the underground after the first human after Chara died, he likely would have been killed before he had the chance to explain himself.
But then it also begs the question: why kill the child at all?
Of course, the human child could have left the underground with the soul of a near-deceased monster and collected the souls of six other near-deceased humans to break the barrier, AND that first human could, indeed have acted as an ambassador for monsterkind.
But hey, I guess it gives the story more realism. "Plot holes" happen because of human (or monster???) error. We wouldn't have a game to play otherwise.