Statement I tells us that "id nimnop" means "We are honest", but there is no direct link to the code for "chess".
Statement II tells us that "gob otsaf" means "They play cricket". Neither of these statements provides any direct information about the word for "chess" in the code.
Since neither statement offers information specific to identifying the code for "chess", it is not possible to answer the question with either statement alone or both together.