Besides, Evan was a 'Hero'. And there were a lot of people who didn't want there to be heroes for reasons only they knew, but that wasn't the main problem.
What the Colonel had issues with, was the fact that the assassination attempt happened in Duscon.
'This is very troublesome.
If it gets out that Evan Eris, the GWE's Prime minister's son, someone with the Alpha Continent's Sword Saint's support was attacked in Duscon, in this state; it'd be bad for us on the International scene.'
At that point, the fact that Duscon should not be held responsible for Evan's security would not be considered. It would not change the fact that he encountered an attempt at his life, in their country.
That's the only thing people would care about.
People would take things at face value, and use it to criticize them, causing problems both internally and internationally.
Rival political parties would take it up with the party Shelde's Governor belonged to and it would delve into chaos.