Similar to what Rick said: Not dying on the hill is the guidance here.
Just ask them how they are using OKRs now (the problem with OKRs is all of the different definitions and they don't all map the same way)
but, whatever definition they are using you can fit it into the system, and I will change my language to match their language for a while.
"So we are going to set some 90 Day Objectives, 90 Day Priorities by following out Rock Setting Process...."
"That Key Result sounds like a nice item to add to an L10 Scorecard..."
blah, blah blah. hope this helps