The Eastern European land Zemenia, where Leyla and the butcher are supposed to come from, does not exist. The language Leyla is speaking sometimes is Polish. The Zemenian flag you can see in some scenes is patterned on the flag of Croatia but in other colors and with some little modifications. Additionally, the symbol on Leyla's hat pin and box contains the Ukrainian national symbol. The Zemenian language Mr. Monk is trying to speak (with the dictionary) is an invented language.
Stottlemeyer says "Last year, we got that conviction on that guy by virtue of the air that he breathed into a beach ball." That was in Mr. Monk Goes to a Rock Concert (2006).
This is the only episode with the "here's what happened" part in a language other than English.
As stated elsewhere, most of the fictitious language spoken is actually Polish. The actress ( Joanna Pacula playing Leyla is Polish after all. Yet, at a bus stop, a woman says "spasibo" which is Russian for "thank you".
The episode is about immigrants who are said to be from a country named Zemenia, but Leyla (the main character of the episode) speaks perfect Polish. In the following scenes the immigrants and Leyla's mother speak Russian.