Yes that is pretty stupid advice! You'd imagine the RSPCA to know more about animals...(?)
I haven't received any silly advice exactly from them, but one day I calle dthem about a dog howling from a shed, which I had heard regularly for hours on many days. I just asked if they could check it out.
I told them this shed was on spare ground, and gave them the grid reference and a fine detailed description of the location, so that no-one who followed that particular little lane could miss it! I told them "There is no house there. It is a collection of sheds behind a 15ft high corrugated iron fence."
So....they wanted the house address and number (what??) I repeated what I'd told them a minute before, and they repeated that they couldn't come out unless it was an actual house and address.
This back-and-forth lasted another few minutes. Then I gave up. They suggested I try the Dog Warden...
Fortunately later I did discover that a farmer owned that bit of land, kept sheep and trained sheepdogs. He had the dogs kenneled there. Unknown to him, I watched him once through a hedge, training one of his pups, and he was good with the little dog and gentle. I watched him with his dogs also, and all the dogs looked cared for and very happy.
That must have been a noisy one!
So I found out there was no cruelty happening.
But what a limp response from the RSPCA!