At the moment you'd need to set up each animation separately, and rely on the two animations playing at the same time. A few alternatives:
- You could set up your tileset twice, once with larger tiles, such that you can animate this door as a single tile.
- You could use an "Image Collection Tileset", and save each frame of the door as a separate image. This option might work best if you have many different sizes of animations.
- To make it easier to set up multi-tile animations, check out the Bulk Animations extension.