In a similar vein to a couple of other forum posters, I am currently having problems with getting SPRequireUnique to work. (I am using SP Online - v15 (SP 2013))
In an attempt to debug my intended new item form, I have created a separate proof of concept list and tacked the following code into the page
errMsg: "This employee already has a record for the selected Skill and Proficiency Level.",
console.log("Require Unique run");
It seems everything is loading correctly as I am seeing the 'initMsg' text below my input field and my console message is being output, but my input just doesn't fail the validation test.
Taking a look at the underlying code, it appears the validation should be triggered when my 'Title' field loses focus but to no avail.
I have tested this both with and without the native SP column setting for requiring unique values and neither setting makes a difference to this function, although the native functionality does trap the duplicate value.
It seems that those who have resolved their issues with this function have done so more by luck than judgement, so any pointers would be gratefully received!