Interlining and ORS

Hello. I have recently set up a route to test connections and transfer times. The route is La Rochelle-Lille-Milan Malpensa.

My flight from LRH (departs 17:25) arrives at LIL at 18:51 and the connecting flight to Milan (which is provided from a different company) departs at 19:58. This is 01:07 transfer time. The whole journey takes 4:50. Once this flight had been booked, I tried to find my route in the ORS and it wasn’t there.

My question is for it to be in the ORS, do we have to be interlining or not?

Yes ;-)