Help - messed up a spell ability and now stuck with nonsense!

Turn away: Duron, Iaus, Merlina and Velven!

During my last session I was sick with plague (a cold) and I wasn't functioning on all faculties.

There are a pair of spies currently tailing the party at the behest of a very powerful noble. The spies happen to be from the same changeling clan as one of the party members, and they have an "identity tag" - a special coin. I needed some way for the spies to be able to track the party.

In my addled brain, I had a genius idea! One of the spies would leave their coin with the party (with the identity scratched out), and then they'd be able to Scry on them, right? That's totally how that spell works.

So yeah. I slept on it, re-read the spell and realised my error lol.

So the party now have this coin, which they have taken as a threat - they assume that the spies know this party member is a changeling and they are threatening him somehow. They're not high enough level yet to be able to Scry themselves, thankfully.

I was thinking maybe a cursed item of some kind? Or maybe it could work kind of how I intended - that this coin in particular has been enchanted to let the owner know exactly where it is, sort of a buffed Locate Object.

I'm open to thoughts and ideas to get me out of a narrative hole!