I just got a platinum eye weight last week. The doc and I talked about it being reversible. I do not know the answer to your specific question, but I would think you can find another doctor willing and properly trained to remove your weight if they think the weight is no longer a necessity. My doctor is a plastic surgeon/ facial reanimation doctor in Charleston, SC.
I'm based in Ohio. I was told the same thing when my eyelid weight was placed. I have to admit my surgeon did a fantastic job. I do not have pain in the area nor has there been any movement of the weight. I think the issue doctors have with removing it is that my facial nerve and muscle control healed with the eyelid weight in place and if they take it out there's a chance I will no longer be able to close my eye all the way. I think this is a fairly small risk considering that I can close my eye fully upside down. Even with the weight in, I do not blink.
But I am experiencing professional setbacks due to the weight being there. If I knew it was safe to approach the magnet, I would leave it alone. But right now my options are to stay away from magnets I need to work on, or try approaching and risk either the eyelid weight heating up next to my eye, or risk the weight being magnetically attracted to the NMR magnet. Given those options, I would prefer to stay away. But this is the field I trained in and what I do and staying away is not a long term plan. It will limit my job opportunities if/when I change employment.
So at this point, I think it's best to just get the weight removed. But now the issue is finding a doctor who I trust to do it.