[cypher]

Those carrot cottages are great for nibbling or playing/climbing on & an extra hideout for when they're out & about but probably not the best for making a nest in & if they get peed on you have to bin them. She might use it if you put a bendy bridge over the door to make it darker inside but if she might still be peeing in her nest for a while yet then maybe not such a good idea to encourage her to use it!
You could try giving her a cardboard box & see if she takes to that.
I'm not really sure which are the best houses available for Syrians in the UK, many people get houses from Rodipet in Germany, the labyrinth or granite houses, but maybe other Syrian owners will have more suggestions for you.