They are interchangeable. The 6922 is the commercial-grade version, a step above the consumer-grade 6DJ8. In practice, it’s been a half-century since the phone company, avionics, or the military used these tubes, and they were replaced by FETs in TV’s by 1970. So they all go into non-critical consumer applications now.
They were never designed for audio use, so distortion and gain can be unpredictable. Testing is always a good idea to make sure they are suitable for audio use.
Quick definitions: consumer grade means it’s no big deal if it is out of spec or fails in use. It just annoys the consumer, nothing more. They go and buy another at the TV repair shop.
Commercial grade means telephone or broadcast use, where out of spec or failure in the field means loss of signal, and substantial financial loss. Think of "I Love Lucy" going off the air in Los Angeles. Like that.
MILSPEC means combat-ready, or aerospace use, where failure means loss of airframe, combat ineffectiveness, or loss of life. That is why MILSPEC costs at least 10x or 20x as much as consumer grade.