The company forced them to train their replacements, who are non-citizens brought in to the do the same job cheaper because the utility is run by people who apparently feel it's fine to sell out their own countrymen to make a buck.
I don't know what's so mysterious about this. It is what it is. The only question is what are you going to do about it?
I have a really simple solution. Abolish corporate taxes in their current form and replace them with a head count tax. Every US citizen is, say, $1000/year. Every legal immigrant is $2500. Every foreign national abroad, including contract workers on outsourced work, gets a fee of $5,000. If at any time, more than 25% of your work is either performed by subsidiaries or outsourcing firms based overseas that has a sales or some other nexus into the US, you pay FICA on your global workforce including contracted employees.
So carrot and stick. A big, incredibly sweet looking carrot and a stick that has nails driven into it because we want to make the choice obvious.