I don't think that was one of the talks that was live streamed, so there won't be a recording. I'm traveling today so I'll have to look for it when I get back. Henry may have a website, I'll look for that too.
Often talks of such nature even if extemporaneous or unrecorded are based on on a line of development that leaves traces elsewhere.
I'm not finding a homepage or blog. None is mentioned in his Wikipedia bio.