I have owned JLC watches for nearly 3 decades (since the late 90s). What I can say is that I have never had a problem with any of my JLC watches being serviced in the US service center prior but NONE of those earlier watches were as complicated as a Duometre or EL2.
From my understanding talking to several JLC reps and JLC headquarters, mostly ALL complicated watches from the Duometre line, Extreme Lab line, Tourbillons, Minute Repeaters, etc...would have to return to the manufacturer for service due to complexity, availability of parts, etc...
This was why I was initially surprised that your Duometre was sent to the service center in Texas. No idea if you the boutique manager spoke or advised you to send it to the service center in Texas but if you would have posed the question here first, I think Nico or myself would have suggested you have it sent back to Switzerland in order for the watch to be serviced correctly and without any further issues.
As for the Independents, I could say the exact same thing. They all would have to return to their respective ateliers in order to have a service or repair done properly.
I have to say one thing. DO NOT have an Independent watchmaker try and fix what you think is a minor problem with your Duometre. I am guessing it was under warranty so having anyone open your watch would void any sort of warranty done and it could get worse.
As for your LE2, I would call the JLC boutique that currently has it and request it go back to the manufacturer REGARDLESS of what they say. Remember, they are staff and NOT watchmakers. They can say whatever they want, but ONLY the watchmakers at the manufacturer actually know what they are doing!!! Sad but true 🤷♂️🤦♂️
If you need any help, I am sure Nico or I can step in and try to give you a hand 👍