The following is based on a decompiled version of Minecraft 1.10 using MCP 9.30.
The tags map_tracking_position and map_scale_direction are only read from a filled_map if it was created by scaling an existing filled map. Besides that the tag map_tracking_position is not even used there.
- Use the following command
→ The scale is the default 3/4 instead of 4/4