You should be able to delete the snapshots without causing any harm. A couple of things to keep in mind --
If the snapshot is associated with an existing backup job, then the next run of that job will result in a full backup instead of a delta
It may take some time for the snapshots to coalesce following deletion, so this could still affect your backups until they are completely removed
If you want to delete the backups associated with the old job, then you can from the Backup > Health tab in XO