A Confusion of Lyons

I received an interesting enquiry today (through my website) regarding a connection between John Lyon of Ryslippe and the Douglas family.  I immediately recognised John Lyon (1510-1592) as the founder of Harrow School, but was not aware of his connection, through the Lyons of Glamis Castle to the Douglas family.

For those not clued up with British geography, Ruislip, to give it the modern spelling, is but a short ride on the Underground from Harrow, in north London.  Glamis Castle is in the middle of Scotland. and a lengthy journey in 16th century Britain. Indeed, the Union of Crowns between England and Scotland was still a century away.

A quick search of the internet returned several sites that make the link. The John Lyon, born and/or married, or who even died in Ryslippe did, indeed, appear to be also Lord Gamis.

But is this really so?

Most genealogists appear to give the John Lyon of Glamis his own genealogy, quite unconnected with Ryslippe or Harrow. This family do indeed have several Douglas connections.

But I think the two families are unconnected. Can anyone add anything to this?