A blowing exhaust will allow air into the exhaust system .. the lambda sensors get confused by the very lean reading due to this air and you will get a fault code .
You said you were waiting on an exhaust to come in stock , hence its logical to assume you have an exhaust leak and an eml due to that.
Thats why i think the eml light is a seperate fault due to an exhaust leak .
The oil is very clean and new looking .. no magic im afraid .. it looks like 3k old oil on the dipstick
Steam is very similar to oil smoke so easy to confuse , burning smell is probably the drive belt rubbing or just the coolant on the exhaust and the steam ..
If you have never smelt hot antifreeze then you could well say its a burning smell ... itrs very pungent.
Over heat is not so good , did it hit the max or just read hot ?
Overall and Porsche engines are pretty good when they get a little hot , its not like a few years ago on other makes when an over heat means warped heads .
That in a worst case senario is a possible .. but we are talking pretty rare .. possible .. but atm i would say dont worry about it .. and i think you are already worrying enough as it is .
For now .. and im of the opinion it is , then its just a waterpump .. dont get an ulcer over this as you have 2 weeks till its even looked at .. worrying isnt good for you .. especially if its for nothing .
Car needs to be recovered .. as you say .. not good to drive it .
Another oil/filter is not needed .
Again a thermostate is not needed , it wont be damaged by this .. might need a drive belt depending on if its rubbed or is old as they will be removeing it to do the pump so only parts cost really .
As they say .. a picture paints a thousand words .. and as i cant see your cars a picture helps me a hell of a lot