Why dont you ask the police science lab who and how and where they did it? how would I or anyone here know? bit of a stupid question isnt it, fact is the tests were done, and testament to scrapping DCIs assertions that the bedding wasnt tested
And you could also, if you find out what they did, and its not to your satisfadtion, advise them on what to do next time

I agree totally. Who here can answer your questions, Carana ? Pretend you're writing a book comparing the police techniques in the EU and may be the Portugueses will open their doors to you.
Madeleine's bedding wasn't taken to the first floor, at least, it didn't have to, unfortunately. The cops were delicate enough not to require the twins' beddings as they yet thought Madeleine had got lost.
About the tests made inside of the crime scene and about the bags that were taken for analysis out of the crime scene, it's like in the UK : no one knows, but everybody trusts.