You shouldn't need to directly reference System.Data.Linq.dll ; the library should pull from System.Core.dll iinstead.
On my end, it works as-is with the includes you've given. You might try calling System.Core.dll without the folder path in front of it to see if it behaves any differently (might reference a different file location/version).
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Ami Barrett
Lead RPA Software Developer
Solai & Cameron
America/Chicago
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