To be on time
'Knowledge Crusades' became the highest priority for human beings. Menteens were very demanding when it came to mutual agreement fulfillment, so Humans' foremost 'must' was to deliver their part on time.
A 'beneficial acquaintance'
Menteens civilization has a twenty thousand years history of constant growth and evolution. They are scientists-creators of the highest level nevertheless Humans appeared to be a 'beneficial acquaintance'.
Not only important but sacred.
The exchange process is not a simple take-and-go deal like we got used to, it is a royal worthy ritual.
A unique technological knowledge was always of the highest importance and protection to Menteens, yet it appeared that Humans have something even more valuable to offer.
Tech knowledge for Universal Wisdom.
Humans' DNA and all information in it - that what interests Menteens mostly.
They know that this bioinformatics material is one of a kind in the whole space-time and that with it one day their civilization will be able to unravel the Universal Wisdom.