And lastly, does the alert reading of the outside of a cable present a dangerous situation in your opinion?
That's perfectly normal when reading the outside of a power cable, but as noted earlier in the thread it's not a 100% reliable test of the cable being powered. That's because you could be sensing on the neutral side of the cable.
However, if you place a NCVT on the outside of an XLR cable and detect voltage, that means the cable shield has at least 40 volts AC on it (and up to 120 volts). That suggest that your mixing console has lost its "ground" EGC if you're powered from house AC, or your generator frame isn't grounded/earthed when running. From all my experiments that's as close to a 100% reliable test as I've found in the field.
Don't do what one of my live-sound students did last summer. I gave out free VoltAlert testers to my graduating students, and one reported that he used it for testing power at a barn dance. He used it during a stage check finding voltage on the microphones, traced it back the XLR cables to the mixing console (of course), then had the VoltAlert beep a foot away from the mixing console surface (30 cm for our UK readers). However, he really didn't believe what it told him, so he touched the console with a finger and got "a pretty good shock". He found that the extension cord the farmer supplied from the barn power had the ground pin broken off. Yikes
Of course, don't use your own body as a backup voltage test. If there's any question at all, the gold standard is a voltmeter checking between a known earth ground and the chassis of the gear or microphone in question. However, you have to be sure there's no paint or corrosion beneath the meter leads when using a DMM. But a NCVT doesn't care about rust or paint and will easily find a hot mic from inches away which is why it's a great pre-show check for "hot" mics and guitars. Again, I've done a lot of experimenting and testing with various NCVT products on sound gear biased to different voltage levels, and this seems to be a solid application for them. See pic below for my NO~Shock~Zone demonstration of measuring a hot mic with a NCVT.