Suggestion is that you look to the moment of the commit. This behaviour can happen with autocommits. So committing on the right time could solve this problem
With the insight provided by both Martin and Ronald my partner methodicly tested. Essentially as far as we can tell, it boils down to this.
On the Order Picking side al works well, as they work through each order individualy and once it is reported finished the commit correctly refreshes their overview.
The backoffice however is working from a "list" which is NOT refreshed, unless they completly leave the overview screen. In order for them to get a correct individual presentation of the order we added a "commit- no action - refresh in client" in the workflow to open the dataview which fixed the problem.