Great video, amazing footage; showed it to my wife and she enjoyed it also.
Dingo, you present yourself very well; clear wording and no needless verbiage. Well done!
"It is wise, though, to remember above all else: rifle, caliber, scope, and even bullets notwithstanding, the most important feature of successful big game hunting is to put that bullet in the correct place, the first time!" John Jobson
As whether that sound will work on the various North American critters mentioned, the answer is YES.
I've called several N. American species with a sound that is virtually identical.
With a tiny reed from a rubber squeeze toy (old style easier to detach) that sounded the same as this sound to my ear, I called coyotes and fox.
The Fox Whistle sound is virtually identical to several calls I've made, and to a sound I make with my voice and lips alone. That high pitched sound has called black bears (too close!), coyotes inside of 18 inches, bobcats, grey fox to within 12 inches, red fox, and assorted birds and rodents plus some I've likely forgotten. I have every confidence that it would call lynx, cougar, grizzly and wolves as well, though for some of those I like a louder sound unless I know one is near. I suspect if it can be blown right, it would call deer and moose.
I would target bobcats in close thicket cover with this call, and foxes, especially grey fox. For coyotes and bigger stuff, if I had another call with me, I'd probably use this one as a coaxer unless the critter was close, and then I'd use this little high pitched sound alone and play it softly.
Do you have a photo of the whistle I would like to make one? We use a similar call made from Turkey wing bones for Turkey.
"When you disarm the people, you commence to offend them and show that you distrust them either through cowardice or lack of confidence, and both of these opinions generate hatred." Niccolo Machiavelli
Yes just called one within feet of me with one. There are several You Tube videos on how to make one. Takes about ten minutes. You can also make them out of shot shell brass. I am going to try a deer antler one but not sure I can get the right pitch. I am also going to try it on deer and Javelinas a rabbit sqqueker works on them so the whistle should too.
"When you disarm the people, you commence to offend them and show that you distrust them either through cowardice or lack of confidence, and both of these opinions generate hatred." Niccolo Machiavelli