The extensions for 5.4 are not working on mac correctly and that probably prevents fiber bundles from loading (check the error log).
If you load as models, you need to be sure to specify RAS coordinates. Fiber bundles are always in RAS because they can also have tensors-per-point that are also in RAS. You can specify this in the options:
Note to @zhangfanmark : if anyone is working on the WMA pipeline code it would be good to add the header flag to the generated .vtk / .vtp files to indicate that they are in RAS so they will load correctly as models by default (more info here, to match the implementation here.