Doing It for the Art: Surprisingly crossed with Executive Meddling. As mentioned on the page for the series, one of the NBC executives ordered the Krofft brothers to hire a linguist to create an actual Pakuni language for the original series. Considering this was a no-budget Saturday morning kid's show, this is the only explanation.
Not completely coincidence. (Wildlife) Marshall Willenholly was Kevin Smith giving a Shout-Out to the TV show. I doubt anyone ever figured Ferrell would end up playing Rick Marshall in any adaptation, however.