I emailed Royal Jordanian (RJ) and received confirmation that qualifying for and maintaining of RJ Royal Club (RC) elite tiers does NO LONGER require RJ segments.

Flights on any oneworld member airline and their respective oneworld affiliate airlines which are eligible to earn tier & award miles will also count as segments. To be eligible for earning tier & award miles the booked fare code needs to be listed in RJ's online mileage calculator.

RJRC tiers qualifying & maintaining (RJRC's T&C seems to have not been updated yet)