That would certainly be unexpected from the metadata call. Are you making any other API calls around the same time?
Also, are you sure this only happens when you're making this metadata call? Is it possible the people with the file are (perhaps not intentionally) saving new versions and causing the conflicts, unrelated to the API use?
Conflicted copies can also occur when a file is left open on another computer, especially when using applications with an auto-save feature. Closing the file from within the application on either computer should prevent further conflicts.
For more information on conflicted copies, see the Help Center article here: