I also experienced what OP states, on several airlines. Usually you just have to see how far you get on your itinerary and when you get stuck, find help. I also have found myself in a few airports, stuck for a few hours, or even nights.
It's not always a bad thing. I found myself once on a Swiss flight that was delayed for no obvious reason known to the average flier. Missed my intercontinental connection, got to the service center, made the guy rebook me on the only possible connection I knew about (he couldn't find it without my help), as it was basically halfway across the Americas extra. In addition, I ended up in a more expensive booking class, giving me over 10000 miles extra, plus a 600 Euro compensation, which made that my flight was almost for free.
I also asked the agent in OSL to just rebook me on beforehand via LH, as it would be seriously more convenient for me and the airlines. They refused. Pointed it out in the correspondence with Swiss, pointed out how it would have been much cheaper for them, ore convenient for me and much less trouble for everyone involved, then got the explanation given in the first paragraph.
What I recommend you do:
1) program the Diamond hotline in your phone. Call them as soon as you notify irrops. see if they can help you via the phone. No guarantees, though.
2) Claim the 250 euro (or whatever it should be) anyway. DO NOT IN ANY WAY mention the planned closure of the runway, the incident or anything else. Do not be an apologist and do not give them ammunition to reject your claim, especially not if you're not 100% certain about some things. In addition: if you knew about the runway closure at HAM, then SK knew about it and probably anticipated on it. That removes the excuse.
So, go on and claim. See how far you get.
I actually once had good luck with getting rebooked when flying from NCE to OSL via ZRH. there was a thunderstorm between ZRH and FRA, disrupting all flight traffic. Agent in NCE contacted headquarters and got a go, so I got rebooked via VIE. Now that's what I call service.
