My thinking is that you can give care from a distance, but certainly not by yourself. And you won’t be the primary caregiver – in my mind that’s not possible as the patient might need you at a moment’s notice.
That being said, the faraway caregiver can be useful to the care process, as maybe that aspect of caregiving can be done remotely – there are some areas where that could be accomplished. Sometimes someone a bit detached from the day to day can see the situation differently and advise either or both the patient and the caregiver.
Also, this caregiver might be able to come in for a short visit and take over the role of primary caregiver, giving the other person a much need physical and mental rest. But, as primary caregiver, physical presence matters!