Playing as a merchant and getting rid of all your funds straight away sure is nothing short of suicidal. No wonder Adis failed him straight away. On short term the mission became borderline impossible if he played as a merchant. I can see Adis' reasoning.
On the other hand, detaching himself from the norm may have just given him the freedom he needed. Both of them are right in this situation: burning down the house to get rid of the evidence gave the MC an alibi for the Blue Wolves. At the same time doing the quest haphazardly costed him a fortune and info that he could still have kept by now. It was both an innovative play but at the same time retarded. If he played his cards right, he could have the Will, hidden the money and kept the alibi.
That play was by no means perfect, it could have gone better. However the fact of the matter is he is now bloodbound to the Blue Wolves. He still has the route and the help of the mercenaries. He can rebuild the fortune by attacking the caravans and then infiltrate Calieri without two suicidal and dangerous double agents.
I really liked this chapter. Both Adis and the MC fucked up, both of them know each and the other did something of value as well as misplay. This enforces on the MC's creativity but also shows his plans have flaws. Meanwhile Adis has farsighted planning to know how retarded it is to go without funds, but his mindset is too rooted in playing as a merchant to see you can have other ways to get things done. I believe the MC will be forced to use Strovon's power this arc, as the King of Assassins will be just what he will need to act in synchrony with mercenaries and bandits, build riches and then using Adis' specialty as a merchant.