The bangle was on Myers' hand. Robbing her of it and subjugating it would be very, very difficult, but still definitely easier than killing Myers outright.
Saleen committed what he saw to memory. Myers was extremely on guard against him. If it had been someone else instead of him, she probably would not have been so prepared.
Lightning spells were only capable of grinding off powers of the Source, while the Crystal Finger was capable of destroying the powers outright, reducing them to pure energy, which was equal to killing a god thoroughly.
Furthermore, the Crystal Finger was extremely overbearing. Any god below level 16, even if they were to not get hit directly by the Crystal Finger, would not have been able to withstand being grazed by the spell. A level 18 goddess like Myers, on the other hand, would end up dead if she were to be hit where the power of her Source lay.
