Re: Pakistani Molvis
Indirectly on topic question.
In Mutah maybe, if you believe in that, but that still needs someone to acknowledge what it is, what intention there is
and it willl not be done in vain.
Other than that, like it is said above, to reduce problems in future, witnesses and paper work is required and Quran also advice that. Albeit it was on financial transaction. Still better to write down nikah terms as at least common sense practice.