Dave - there re two different issues in your questions.
1. For those cemeteries that are "in the water" just report them with URL to BG support. I don't know what they do about them but I have reported quite a few over the past couple of yeras. Nothing else you can do about them.
2. For grave markers tha are misplaced if you know which cemetery it should be in, and that is confirmed by its position on the gps marker map, then you can easily move it to the correct nearby cemetery. Open the record in old Transcription screen and down at the bottom you will see "change cemetery" click on that and select the correct cemetery from the dropdown menu. Save that and check that the change is made by opening the record again in transcriptioni mode. If the correct cemetery does not appear in the list, reply back here with the URL and the location of the correct cemetery and I can maybe fix it.