Well, the fact they are more aged does not mean they may not want and be still able to do something (well, OK, I am thinking around 65 or something like that), though indeed I would not expect them to have the same stamina as Marc and his friendsMaybe both? There's something appealing about a hot MILF nurse who also gives her patients sexual favors... though personally I'd prefer it if it weren't old dudes.
So, plenty of options if Zorlun wants to give the possibility of some lewd content (e.g. what about a warden/nurse/doctor/employee making her do something, and decide it is not nice the patient is left out of the thing ? Or viceversa, her deciding to give someone, or even more than one, a bit of youth, and a warden/nurse/doctor/employee or more taking advantage to participate ? Don't forgetting can involve also woman or women, maybe even giving the possibility of having something involving men and then even something involving a woman or women ).
Plus, one could add up an extra possibility, though I admit with a bit of a dark side - there are places where they have not only old people, but also people who are sick, unfortunately often with terminal ilness for which they give only palliative care to avoid the pain.
But there are also places/associations, which help not only elderly people but in general sick people who need assistance and cannot afford it, and that would not require the dark side I just mentioned - it is sufficient for one of those organisations to have their own house, and that could give coherence with what indicated in the choices, while also allowing for the possibility of not having only old people as residents.