United Arab Emirates
I have the Tilsit french version of Kahuna and have always played with the french rules where the three rounds end the same way.
Today playing on yucata.de i found that there is one additional turn after the end of the deck in the third round.
Here on BGG there is a file with a translation by Rio Grande:
When the last card from the face-down deck is taken at the end of the third round and the last of the face up cards has been taken, each player takes one additional turn (without taking cards).
Is this the official rule?
Was the french translation wrong?