Get_wf_neb_from_structure workflow produces run_dest_root KeyError

The get_wf_neb_from_structure workflow runs the initial optimization in vasp fine before the neb run. However when atomate.vasp.firetasks.neb_tasks.TransferNEBTask firetask runs subsequently, a KeyError occurs. This leads to the firework being classed as fizzled. Any suggestions as to the cause of this would be greatly appreciated.

    from atomate.vasp.workflows.base import neb
    additional_spec= {"site_indices":[0, 1], "is_optimized":"False"}
    cl_neb_1 = neb.get_wf_neb_from_structure(structure,additional_spec=additional_spec)
    cl_neb_1 = add_tags(cl_neb_1, "AlP4 plane Li neighbours")
    launchpad.add_wf(cl_neb_1)
    "_stacktrace": "Traceback (most recent call last):\n  File 
    \"/home/zccaayo/.conda/envs/atomate/lib/python3.7/site-packages/fireworks/core/rocket.py\", line 
    262, in run\n    m_action = t.run_task(my_spec)\n  File 
    \"/home/zccaayo/.conda/envs/atomate/lib/python3.7/site-packages/atomate/vasp/firetasks/neb_tasks.py\", line 55, in run_task\n    dest_dir = 
    os.path.join(fw_spec[\"_fw_env\"][\"run_dest_root\"], wf_name, label)\nKeyError: 'run_dest_root'\n"```