JFYI, it is only the English/American that use quid pro quo in that sense, in Latin (like in many other languages) it has a different meaning, while do ut des has that meaning:

https://en.wikipedia.org/wiki/Quid_pro_quo

"The Latin phrase corresponding to the usage of quid pro quo in English is do ut des (Latin for "I give, so that you may give"). Other languages continue to use do ut des for this purpose, while quid pro quo (or its equivalent qui pro quo, as widely used in Italian, French and Spanish) still keeps its original meaning of something being unwillingly mistaken, or erroneously told or understood, instead of something else."

I think all Americans know what "quid pro quo" is. A President was impeached for that. It was most likely the impeachment of the century.

The literal meaning is "what for what?".