No
The original post is "if Lokir was executed
because he stole just one horse, why do we only have to pay 50 gold?"
2 other posts before your 2nd post here revolves only around that
As for "get rid of the unknown", I call crap
Because they managed to know
who Lokir is: Lokir from Rorikstead. There must be some sort of identification beforehand.
Even if they don't know, getting rid of the unknown is not exactly the best course of action. Good if we're just another Stormcloak. Bad if we're actually Thalmor spy. Even worse if we're actually Imperial spy
Delaying execution to gain further confirmation is the best course of action. Scratch that, the best course of action is to interrogate the "unknown", because they have a torture room right there in the dungeons
Executing Ulfric should have been top priority, because Ulfric is well-known to be the root of the Stormcloaks. No Ulfric No Stormcloaks.
Besides, each and every prisoner has already been tied. Still armored, perhaps, but bare-handed. No amount of "reacting" will make matters any worse. They were in an Imperial controlled-area. Archers everywhere, guards in every gate