Chyron.
But I didn’t see it in either of your links (?)
EXCELLENT CATCH! Both links WERE to the one without Chyron. I screwed up. Here are the links to the different versions. My apologies for the confusion.
Without Chyron
https://www.youtube.com/watch?v=ZCoZwq-uefU&list=PLYTtL1FB2XCooAYmmy31Wlo6SM4_sWqKS&index=1
With Chyron
https://www.youtube.com/watch?v=_W8E911f7Ec&list=PLYTtL1FB2XCooAYmmy31Wlo6SM4_sWqKS&index=2
No matter how much I tried, I couldn’t make the thumbnail show the chyron strip. YouTube keeps cutting it off the thumbnail, even though it shows when you play the video.