Instead of HOME_ROOT/.vnc, /root/.vnc should be used
for user root's home to specify default file context
as HOME_ROOT actually means base for home dirs (usually /home).
#
HOME_DIR/\.vnc(/.*)? gen_context(system_u:object_r:vnc_home_t,s0)
-HOME_ROOT/\.vnc(/.*)? gen_context(system_u:object_r:vnc_home_t,s0)
+/root/\.vnc(/.*)? gen_context(system_u:object_r:vnc_home_t,s0)
/usr/sbin/vncsession -- gen_context(system_u:object_r:vnc_session_exec_t,s0)
/usr/libexec/vncsession-start -- gen_context(system_u:object_r:vnc_session_exec_t,s0)