The heyday of MSOR program as a substitute for MFE was a decade ago. Look at
the Tracker for historical data.
At that time, many people applied to MFE, did not get in but got offered admission in MSOR instead.
The fact that many students can take same courses under IEOR dept gives people the idea that using Columbia name will be enough to get them a golden job.
Do not forget that Columbia MFE graduates are finding it hard to find job as is and there are several master programs under IEOR with hundred plus class size.
You want to give yourself all the advantages you can if you want to have a chance.
Yes, you may work really hard and smart to get the QT/QR job as a MSOR graduate. I don't know you personally to dismiss your chance.
That doesn't mean I would recommend MSOR as the optimal path for this. Do not gamble and pray for the best.