I thought this was starting to look vaguely familiar! I looked at the early generations of this family several years ago (connected to CORTEEN), and if John was the son of Nicholas Kinnish, which looks likely, this was his grandfather's administration: www.iomfhs.im/lawsons/twill/1734_004.html

And this was possibly his father's decree (not yet seen or transcribed): KENNISH, Nicholas 1784-1 Lon E d 0106398. That last number is for the LDS film which contains this decree. If you order and transcribe it, please add it to the list! See also the other Lonan Kinnish wills there which might be of interest to you. They often mention siblings and other relatives, even if not closely related.

This was the will of Nicholas's grandfather John Kenish/Kinnish (whose wife and son both predeceased him), after which he moved to Maughold: www.iomfhs.im/lawsons/twill/1737_016.html

"Ittm he left and bequeathed to his two grand children in balldoon vizt Nicholas and Margt Kenish twenty shillings to be paid them when they come to ye age of sixteen or seventeen years..."

Son of John KINNISH & Alice CRAINE:
5. Nicholas bapt.16 Jan.1694/5 “Nicholas son of Jo : Kinish” married Christian Tear 28 April 1724 Malew [after his death she marr. John Kewley 1735 Lonan]. The Maughold will of John Kenish who d. 3 March 1736 mentions his two grandchildren in Balldoon “Nicclas” [Nich s/o Nich b.26 May 1729 Lonan] and “Margt” [Margt d/o Nich b.29 Sep.1732 Lonan]. The Lonan will of Alice Kinnish als Crain of KK Lonan d.14 May 1726 mentions her dau-in-law Christian Kinnish als Tear.
www.iomfhs.im/lawsons/twill/1726_010.html

This Kinnish family originally came from Braddan, but several members moved to Maughold in the early 1700s, and Nicholas went to Lonan.

Sue