We've seen another ghost location before

I saw someone in another post saying it felt too convenient for the plot that there were ghosts at the hospital and the school. I feel like they're setting it up to be something way more sinister, where ghosts are trapped everywhere someone died in town. Because the characters do have a throwaway line where they mention there could be ghosts trapped all over town, when discussing trying to get the hospital ghosts to go into their scars. Also something I remember from S2 is when Janet went back to the farmhouse in Maddie's body, she sees her father digging in the yard. Who we know is deceased. We also see her hiding in the closet while someone walks up the house steps, and I assumed that was the ghost of her father too. We also know that people alive can only see ghosts in the places they've had a near-death experience(crossed over but came back) at. Ie, Xavier can see hospital ghosts, and Maddie can see the school ghosts. We also see Janet's grave listed that she died April 30th 1958, but the fire was Jan 14th 1958. Could this just be an oversight with production design, or is it a small detail for later? Is it possible Janet had a near-death experience at her home, and that's why she can see her father's ghost, but even if she crossed over twice, why would the date on her tombstone be almost 4 months after her actual death at the school. I also think if Im right, that her father was an actual ghost at the farmhouse, its the first time we see a location with a ghost get destroyed when she burned it down. So whatever happened to her father's ghost, may help them figure out what's underneath the school. One other thought, Janet's door is the farmhouse door, but I don't know if it has any significance to this theory.