I killed 4 dragons in Southern Elsweyr this morning and didn't get an event ticket. I had not logged in since yesterday before it reset, so there's no chance I got it yesterday, and I know I had 8 tickets yesterday and still 8 after those 4 dragons, because I was planning on buying berries today.
One dragon kill in Northern Elsweyr got the ticket no problem, so just Southern Elsweyr seems to be affected.
Guild Master at
Black Market Wares on the PC NA server.