I am creating a tileset for a 2D platformer in Godot v3.1, however, I seem to have run into something I'm not sure how to fix. I followed this github post on creating one and I managed to copy the bitmask exactly for my platformer tileset.
The issue: SLOPES!
Auto-tile working properly:

Auto-tile not reacting to a different tile:

How would I get the auto-tile to react with other tiles (i.e. connect to the slope in this scenario)? Or at least control how the auto-tile works in specific scenarios. I assume adding it to the bitmask somehow would probably not work as then I couldn't control when a slope would appear or a one-high wall. Any ideas or workarounds?
Note:
The platform is an auto-tile and the slope is part of an atlas.