you can fix it. The place you brought it to doesn't sound like they have the expertise. it will take a while to get the humidity back to where it should be, then I would use an oil treatment. If the neck is lumpy it can be sanded, if the neck straightens out, then a fret job would do wonders. I have an old ebmm that I fight all the time. The truss rod does nothing so I have to keep 10s on it to keep it straight and prevent it from back bowing. The string gauge is a factor. In the summer the neck is pin straight so 9's or a mixture of 9's and 10's work. (10-13-17-26-32-42)........ In the winter, it's a different animal and it's 10-46. I keep my guitars in a dedicated space at 50% and they are in their cases.
I always go back to this table on the Elixir web site to help with the string tension numbers.
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