Why was the 10 Years of Euros Cash made for San Marino? [solved]

This is the only one of the joint issue commemorative €2 that was issued by one of the "micro states", the small countries that legally use the Euro but aren't actually EU-members.
Does anyone know why San Marino minted this coin?

Why does San Marino issue €2 commemorative coins at all? To sell them at profit …

I know that they make the coins to sell them to collectors. 

My question is why San Marino participated with this joint issue coin, when all other joint issue commemoratives have only been minted by the EU-countries.

Easy: They did not participate in the joint issue. They just decided long after the joint issue was announced (for commercial purposes) to issue a coin that looks like it is part of the joint issue, but it actually isn't. That is also why most “official” collectors boxes distributed by e.g. Lighthouse and others have room for the all coins of the regular joint issue (including the ones with the 5 different German mintmarks) but not for the San Marino one. 

Thank you, Master of Coins! 

On the website of the ECB I noticed that San Marino was the only country that didn't issue the coin in January. Because on there it does list it together with the other countries.