They kidnapped my banjo on April Fools' Day

I arrived at my office on this fine, April 1st morning and discovered a ransom note, hanging from my office door by a banjo strap.

We have your banjo.

If you ever want to see your precious banjo again prepare 300 unmarked AgileBucks and dial 847-699-XXXX for the drop point.

No cops.

I rushed to my banjo case; the one I keep my spare banjo in so I can do some early morning practice at the office. Opening the case, I discovered that my banjo was gone and that it had been replaced by a rock. A mocking rock that laughed at me and glowed with the message "BEWARE!"

It was clear that the kidnappers worked for AgileTek. They wanted to be paid in AgileBucks; the currency that we use for our rewards at AgileTek. (Click on these pictures...

...for a little background on AgileBucks.)

What to do? What to do?

(To be continued.)

Update:

I prepared three bundles...

...and made contact with the kidnappers. I got my banjo. They got their bundles of AgileBucks. As instructed.

Almost exactly as instructed. I mean, the note did say "unmarked," right? So I made sure that all of the AgileBucks in the middle of each bundle were totally, completely and without a doubt...unmarked.

Happy April Fools' Day, you rotten, banjo-thievin' scoundrels!