Checking in as Duggan (The Jackals mistakes take 2)

After he was warned that his cover had been blown, Jackal decided that it was safe enough to use 'Duggan' one last time before turning into 'Lundquist.' So, that night he checked into a roadside hotel, knowing full well that the police would investigate his presence there the following day. He even told the hotel receptionist that he would be staying for two days. But the following morning, bright and early, he left, before Lebel and the police arrived.

He was told that the Jackal was blown, not that Duggan was blown. He assumed (correctly) that they only had the name Calthrop at that point. If the French had the name "Duggan" the contact would have used that name. It wasn't until he was at the Hotel in the mountains that he found out that Duggan was blown too. He knew that the contact would give him warning. He also knew that he only had so many fake identities to fill up so many days.

Per's passport photo would show a man with dark hair and it would be odd when he checked in to not look like the passport photo and he had no real chance to dye his hair. remember the photo on the passport is the real Per and the hair difference would make someone looking at it question whether it is really him in the photo (the glaring discrepancy would cause the clerk to look more closely than if the superficial resemblance were passable). he had no good options at that point. I think he should've just tried to hole up at a flophouse or whorehsomething rather than checking in a hotel