Hi, you should 
1) select the dogpark in editor
2) at the bottom left click View on openstreetmap.org
3) Click on Changeset #152017530

https://www.openstreetmap.org/changeset/152017530

Then you'll be able to read the changeset comment and contact the author in the comments, he'll get an email notification.

Notes are usually overlooked and not the best place for such questions unless it's something really old, the author doesn't map anymore and attention of currently active mappers is required.