On the map in my Exiles of Ashrkim world there is a map for Milborne. The Milborne map has circle icons for each location. If you click on one it will display the first item linked. In the case of all of them it is the location article, but if you click any other ones (such as the myth on the temple icon) it will not display it.
Look at the temple on my Exiles world Anvil. You can only see the first of the articles (the location) but you can't load the second one (myth)
Hey, thanks for reporting! I have reproduced and noted down the issue and we will resolving it alongside our next version of Maps - until then a workaround you can use is mentioning or adding an article block of the Myth or other article in the first tab (the location article).