This issue is caused by outgoing-labels list enclosed in outgoing-labels container. Because the list and its parent share the same name yangtools xml parser fails to identify the correct end of the list.
There is already fix merged for this issue for yangtools 2.0.8. See https://jira.opendaylight.org/browse/YANGTOOLS-890 for bug reference in yangtools.

Until HC bumps to yangtools 2.0.8 we can rename the list to outgoing-label as a workaround.