Probably the same reason why you asked if it was loan or permanent transfer. It's obvious Liam wanted out of Basel, as they haven't suited his playing style and dissed him last year by playing him at wingback.
The risk is on the flipside of your second paragraph, and I don't want to delve into the bad side of the "what if's" as the ink has barely dried.
But I can guarantee you, with 1 year remaining on his contract with Basel (after the loan)...I don't need Spitfire to confirm this, but I would believe the plan is for Liam to tear it up at PNE, and not have to go back....
I respectfully think the Basel chapter is closed.