>>/138593/
http://archive.today/2021.04.13-091424/https://www.youtube.com/playlist?list=PLXdFbrsClLQ9WhJ_O1SRYLnD5FmOOfLov
This caption contains 572 video links out of 576 that were added by that time. Or do you mean, out of all entries only 200 are currently downloadable from youtube? Do you have an actual list of 800+ video IDs from somewhere or just recalling from memory? Try looking up missing links through youtube archives:
https://findyoutubevideo.thetechrobo.ca

Other playlists from same channel
(found here: http://archive.today/2017.11.17-223842/https://www.youtube.com/channel/UCj_UmWzyMhrNgs1Q3W-aOGA/playlists )
	[song]
		https://www.youtube.com/playlist?list=PLXdFbrsClLQ_9R2Bl9knZEYYj8FdvGL09
		https://web.archive.org/web/20230413061945/https://www.youtube.com/playlist?list=PLXdFbrsClLQ_9R2Bl9knZEYYj8FdvGL09
	[˛₍˴◅ˋ)੭]
		https://www.youtube.com/playlist?list=PLXdFbrsClLQ9Cwzd2neA0nRSitfv_-CGM
	[best]
		https://www.youtube.com/playlist?list=PLXdFbrsClLQ9xmcGYLD_gD7fVxcSjnI34
	[m3]
		https://www.youtube.com/playlist?list=PLXdFbrsClLQ9VhQmUTbrBTk6jriaDqplj
	[Liked videos]
		https://www.youtube.com/playlist?list=LLj_UmWzyMhrNgs1Q3W-aOGA
		https://web.archive.org/web/20191205221214/https://www.youtube.com/playlist?list=LLj_UmWzyMhrNgs1Q3W-aOGA (caption exists, but page is dead)