Seems like something not to dissimilar to the Horizon Post Office issue, and this person has been caught up in the system. Both the Post Office and DWP are run as businesses. All politicians can do is shine some light on issues - and if necessary change the law. It's a grey area between how much an MP can get a system changed because of an issue. If they could then they'd be accused of frigging the system to suit their own political decisions.
Even so - bloody ridiculous.