Interestingly, I came across the same list just now. It is an incredibly poor one.
For starters, the UK is on the list, which was kind of my point. By even allowing the referendum in 2016 (and making its commitments to NI), it already goes quite a way beyond what many other countries are willing to do.
The Canadian supreme court ruled that Quebec could not unilaterally secede (ie run an independence referendum without the consent of the Central government) ie, similar to the ruling today. Whatever Ethiopia's constitution says, the central government's response to what admittedly seem like ill-thought out regional elections in defiance of the central government has been.....years of wars and war crimes. The Moldovan example is particularly specific to two regions and Moldova has gone to war to try to integrate the territory back into its territory. It still does not recognise any attempt to secede.
The PNG example is of the central government signing an agreement with a minority region to hold a referendum at a specified date, just as the UK government gave to the Scottish one.
The French example is again, a very specific example of the central authority allowing a specific territory (New Caledonia) to have referenda at a specified date, not to unilaterally call referenda whenever it chooses. And it came after a period of violence.
Even this shoddily put together list provides almost no examples of countries where someone other than the central authority provides the legal basis for an independence referendum.