See, once I post what I did, the conversation probably stops, doesn't it.
Because, I did find a solution, but I was interested in what other people would do in a similar situation.
FWIW, this was the solution today.
We got to the restaurant, I got the DC to take off their outerwear. DS was wearing a long coat so not that much of his bottoms were wet.
I took DD to the toilet, found it busy with strange men there.
Now, I'm not in the habit of travelling with clothes for my DD as she so rarely needs them. I do, however, travel with spare bottoms for my older boy as he sometimes has accidents still.
So, I had a spare pair of shorts in my bag, massively too big for DD, but still, better than notheing. Unfortunately the rain had soaked through my bag also, so they were wet too, but not anywhere near soaking like the skirt.
So DD and I traipsed back through the restaurant, got the shorts, back to the toilet, held the shorts under the dryer till they were acceptable then changed, back to table.
We were at the hand dryer for a while - moving out of the way when someone needed to dry their hands. I was aware, standing there, that a couple of the men seemed a bit uncomfortable with our presence, and standing there I got thinking about us losing our men-free spaces and what it means in small ways.
I'm well aware of the big arguments about the dangers of predatory men accessing female spaces, but today got me thinking about all the small ways I take access to men-free space for granted, and not only do I not want to lose it, I don't understand the "etiquette" of the new unisex spaces, I wondered if anyone else here did.
So far, I seem to be learning, if we don't like it, go home. Which seems a shame.