You will not know until everthing is back together and runing again.

Ounce it is going again if you can I would let the Wife drive another Car while you drive the Mercedes for a few weeks and monitor the temp.

One of the things that has happen to me when an Engine over heated is that it loosened stuff inside of the Engine Coolant system and that stuff circulated into the Radiator core.
I have also had a Thermostat go bad win in a week or so after an overheating (also due to a belt issue).

You need to investigate deeper why the Belts came off. May be you Crankshaft Damper is haveing some issues.
Going by a construction sight do you think it is possible something came up from under the Car and got between the belts.

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84 300D, 82 Volvo 244Gl Diesel