Hi Taz60
So glad to hear that your sister's appointment went well. That must be a relief to both of you. Didn't the issue of housing benefit come up when you filled in the original form- because a friend of mine confirmed with them that she wanted her rent sent directly to her landlord? I can't tell you what you should do - but I would ring the helpline and ask.
BIS
Nothing on this board constitutes legal advice - always consult a professional about specific problems