A couple things for your consideration:
1) Sylen could be nicer but he also wasn't any "meaner" than you were. You were the one who opened the door about people not paying attention. Is it ideal customer service to mirror the customer's own snarky manner? Probably not. But Sylen is good at tech support if you can look past the bluntness.
2) Your report was not very detailed. Quests are always activated by selecting the rally marker in the yard of that POI. Until that marker is activated no changes or reseting of the POI occurs. That is one of the failsafes in place so you can cancel a quest if it happens to take place in a POI you are using as a base. A second failsafe is that the rally marker will not activate and reset the POI if there is an active bedroll or claim block inside.
You stated you did not activate the Rally Marker so did somebody else? If they did can you be sure your claim block and bedroll were currently active?
If the POI was reset the moment it was selected as a quest location that is a bug and not normal and I've never seen that happen for any quest.
If the POI was reset when the rally marker was activated and an active bedroll/claim block was inside then that is a bug.
If the bedroll/claimblock became inactive without a new bedroll/claimblock being placed then that is a bug.
If any of the above turns out to be true then they are bugs and need to be reported in the bug pool. Just bringing them up here complaining that the dev team isn't paying attention invites the responses you don't want and does nothing to get the needed information to the people who are writing tickets for the bugs to be fixed. Now, to be fair to Sylen, he did give you a workaround that you can use in your server. Workarounds are what the support forum is all about. You want ideas to keep your players happy until a particular bug gets fixed, nobody is better than Sylen and he gave you a great temporary fix but if you want the problem fixed fixed then report it in the bug pool with more clarity.
So as bitter a pill as it might be to take Sylen's advice to work out some details about the situation and see if there is a cause that is reproducible and post that over in the appropriate place, it is the correct instruction that he gave you.