I'll take the test-for-test — joining the Bobbing Bob group now and I'll keep it installed and open it for the full 14 days. I'm also the developer of PeerPlay, a free reciprocal-testing exchange for this same Google Play requirement, so if you'd rather not track the swap by hand, you can add your app there and get testers in tracked 14-day rounds. Send me your app's link if you want me to return the favor on mine.
https://play.google.com/store/apps/details?id=com.testerhub.app