L.s.

Using Global Simple Search I see that the output is not subject of the language filter:

{mlang en}

Use the Influencing Guide

{mlang}{mlang NL}Gebruik de InterventieWijzer{mlang}

As well as the generico filter:

{GENERICO:type="Tab-start",Tab title="Nederlands"}

Do note the outline and other top bar links This presentation can also be viewed in an app on your mobile device, though offline playing is not allowed...etc.

How to enable that?