Depending on the time of day, an albergue will probably suffice, you're not staying longer than a few hours I guess, let the hospitalero know on your way out and the un used bed can be used by another pilgrim.
You never know their circumstances - they might be pitying you.
I remember on a flight taking off from Istanbul and the two elderly people next to me had high levels of BO. They didn't realise it (perhaps ?) but they described their very busy...
Be creative. As a paying customer, there are enough publicly accessible places in SdC you can do a quick wardrobe change, and give yourself a quick and discreet 'bird bath' in a wash hand basin to freshen up enough to be squez against other...
That service no longer exists. Casa Ivar has taken over that space, and there are no longer showers.
Here's a screenshot from an old Google Maps streetview
This is a more current photo from Google Maps photo gallery of Casa Ivar.
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