While /export includes the ip neighbor discovery stuff, /ip neighbor export, /ip neighbor discovery export, etc, don’t work properly.
[jmaslak@edge2.foo1] /ip neighbor discovery> print
Flags: X - disabled
# NAME
0 ether1
1 X ether2
2 X br_ext
3 br_workstation
4 lo
[jmaslak@edge2.foo1] /ip neighbor discovery> export
# jul/25/2016 01:45:45 by RouterOS 6.35.4
# software id =
#
[jmaslak@edge2.foo1] /ip neighbor discovery>
In this case, the export should have contained entries for the two disabled interfaces.