Entered RG at ~20mins before reset, and reset happened whilst fighting King Castle Golem. After boss died, the NPC didn't spawn to give quest etc or tele to bonus maps.
Did you kill the boss on the far left side? Because the issue tends to be killing it too far left, not because of reset.
No, boss stayed middle the whole time since NL RG you just stand at spawn. Boss died and dropped standard totems/etc drops. Afterwards timer kept ticking down, but Cecilia never showed up. I could still stay in the room and attack/kill the golems but nothing changed.
You should be fine on the two right side teleport points. Just don't let boss go to the two left teleport points.