I have the almost similar problem. The 100-miles badge was only earned on my first activity reaching to 100 miles. All other activities that reached or exceeded 100 miles no longer earn the badge. I have tried activate and/or deactivate elevation correction but still not working.
If you correct the distance manually, you won´t receive a badge either. It´s somehow understandable to prevent cheating. And bad, if the recording was not exact and your 42.09km does not count as a marathon.
My educated guess is, that the elevation correction is accidentality evaluated as a manual intrusion.
That seems not to be right. Yesterday, I got this problem again. I activate the correction, badge is gone. I delete the activity, upload it again, edit the elevation manualy (by leaving the correction deactivated) to this value the correction does normaly, and the badge is still there.
But in case of editing the distance, you are correct.
