Never heard of Remington Mill specifically, but the pattern you're describing - if it matches what I'm reading between the lines - is fairly consistent with industrial site reports across the board. Old mills are particularly active locations from an EVP standpoint. The combination of residual stone memory, layered worker trauma, and the acoustic properties of the machinery halls makes them almost ideal environments.
I've done overnight sessions at a couple of decommissioned factories up here in Newcastle and the results were notably different to domestic haunts. Less dramatic, but far more consistent. Repetitive audio phenomena especially.
A few questions before I can offer anything useful:
What county exactly? Forsyth County covers a reasonable area, Are the reports centred on specific areas within the structure, or distributed throughout?, Has anyone attempted a systematic EMF sweep rather than just reactive readings?
The shadow people reports at industrial sites tend to correlate strongly with areas of electromagnetic irregularity - residual wiring, old transformers, that sort of thing. Worth ruling out before you start building a narrative around it.
If anyone's done a proper baseline sweep with a Trifield TF2 or similar across multiple sessions, I'd genuinely be interested in the data rather than the anecdotes. Not dismissing the experiences - just think the more rigorous the documentation, the harder it is for sceptics to pick apart.
What's the access situation like currently?