Importing Armature/Skeleton from Blender to Godot the last bone is invisible

Question

Blender 2.79
Better Collada Exporter
Godot 3.1
Godot Project in Github

When I export 3 bones from Blender to Godot the last bone never appears. However, all three bones do appear in the Skeleton. I use the third invisible bone as the Tip Bone in the SkeletonIK node.

The IK seems to like the target placed at the base of the third bone.

The IK sort of works. But with a lot of movement the meshes don't stick to the bones and the target gets out of whack.

Is there something wrong with the import? Should the third bone be invisible?

Blender view (note the bone sticking out)

Godot views:

Comments

There is little documentation regarding SkeletonIK so I used a simple function that calculates the IK for my particular case (see the github repo listed above). I still haven't found out the following questions (but would like to someday):

• Why does the last bone not show up in Godot? Does it matter? It there a reason for this?
• Why do the meshes not stick to the bones? Sometimes it works, sometimes it doesn't.
• What do the different parameters in SkeletonIk do? The documentation just lists them without any explanation.