attaching a lanyard to the tracker?

Here’s an easy way:

1. Get a piece of string - ideally, thin nylon string like for a fishing line.  
2. Thread it through the hole in the tracker.
3. Push it through the lanyard loop.
4. Thread it BACK through the hole in the tracker in the opposite direction.
5. Pull on the 2 nylon strings together to pull the lanyard through.

Voila!

If you don’t have nylon, any kind of thread ought to work - you may have to double or triple it up if it’s just sewing thread.

If you have one of those thin metal needle threaders, like what come in hotel sewing kits, that MIGHT work.