ID 370757 - Animations exported as glTF are not correct when viewed in glTF viewers

Problem summary
Animations exported as glTF are not correct when viewed in glTF viewers.  

Customer reported version
Modo 12.1v2

Customer reported platform
MacOSX 10.13

Steps to reproduce

1) Create a cube and rig it with a single joint.

2) Animate the rigged cube on two frames. 

3) Go to Preferences -> File I/O -> glTF v2.0. Make sure all settings are set to default. 

5) Go to File -> Export As. Select to export as glTF v2 to a location.

6) Open a web browser and open the file in a glTF viewer. For example this one: https://gltf-viewer.donmccurdy.com/

7) The animation of the imported cube should look the same as in Modo. However, the animation is incorrect in the glTF viewer. 

Workaround
Unknown workaround. 

Reproduced by support

This bug has been reproduced in:
Modo 12.1v2 - MacOSX 11.13 - CentOS 7 - Windows 10 
Modo 12.1v1 -                                                  Windows 10 - regression 

Unable to reproduce bug in:
Modo 12.0v1 - MacOSX 11.13 - CentOS 7 - Windows 10 

Earliest version tested
Modo 12.0v1 - Issue no longer appears in this version and has regressed. 

Expected behaviour
Exported glTF animations should look identical with the animations created in Modo. 

Actual behaviour
Any glTF animations exported has a different transform to what was created in Modo.