Generate Lightmap UVs Fails Very Frequently on FBX Imported Meshes

Generate Lightmap UVs fails very frequently on FBX imported meshes. 

Found in 4.22 CL# 7053642, 4.23 CL# 8386587, 4.24 CL# 8971176

1. Open the Editor
2. Import any of the FBXs in the attached file
3. Open UV Channel 2 of the imported mesh
4. Place the mesh in the scene and build lighting

Results:
There will be a dense cluster of overlapping lightmap UVs in the top left corner and when lighting is built it will give bad results

Expected:
Proper light map UV is generated reliably