Not necessarily, but possibly. Sometimes its just a bad connection when you screw the bulb in and one type works better than the other. Its surprising that the CHE didn't work. Those rarely fail. I'd check both of those bulbs and a working bulb in another fixture before throwing them away.That’s good to know incase it happens again 😊 surely if it was the fixture the mvb bulb wouldn’t work in it either? 🤔
I buy my incandescent basking bulbs in 6 or 12 packs just for this reason. They always burn out at the most inconvenient times. I like to have several on hand to replace any that fail. I've used 100's of these bulbs over the decades, and dozens of fixtures. I've seen many types of failures for many reasons.