Nipype cannot detect FSL installation

I have been attempting to set up Nipype for the first time recently. I have a Ubuntu 18.x subsystem for Windows, and I have installed Nipype solely through this terminal as outlined in the installation documentation.
I have also installed the latest version of FSL, located in /usr/local/fsl. However, despite the installation, running the Nipype install test (on the Nipype install page), returns an “FSL_test”; “Fsl not installed” error. I read other posts here attempting to troubleshoot the issue, which formerly was resolved by adding FSL to the path of Spyder/Conda, but I am not currently using either of these. I did add FSL to my Ubuntu terminal path manually in an attempt to resolve the issue, but that had no effect. FSL runs just fine and can independently be called with no issue.

Am I missing something here? Is Spyder/Conda necessary to pair with Nipype?
Your support is appreciated.

@pytest.mark.skipif(no_fsl(), reason="fsl is not installed")
def test_fslversion():
    ver = fsl.Info.version()
    ver = ver.split('.')
  assert ver[0] in ['4', '5']

E AssertionError: assert ‘6’ in [‘4’, ‘5’]

/home/[UserDirectory]/.local/lib/python2.7/site-packages/nipype/interfaces/fsl/tests/ AssertionError

Dear @flanaglu

Could it be that fsl is actually ok and can be found by nipype but the assertion test looks for the wrong version?

Kind regards