I'm not familiar with Texas Shield, though I am active with Armed Citizens Legal Defense Network, which is not insurance per se (
www.armedcitizensnetwork.org).
The argument that having a plan in place for such an emergency means you were planning to commit murder, is a little like arguing that if your home is insured against fire, you must be an arsonist. I would expect a good lawyer to shoot it down for you.
If the case goes to trial, the figures you quoted are probably on the low side, unfortunately.
best,
Mas