Theories on the location of a 'dead rat' in my CIT office room

Since yesterday, i have not managed to find a 'dead rat' (that is if it is) in my School of Computing and Informatics Technology (SCIT) office room.

Since then I have developed and encountered several theories about the dead rat's location. One of my colleagues had a theory that the currently unseen rat was imported from elsewhere in a boxed package. So, we got rid of the big boxes and their contents. But the smell remained. Another theory is that it could have died under one of the bookshelves. We checked and noticed that the location under the bookshelves had not been cleaned in a long while. The "under bookshelf theory" was extended to suggest that the dead rat's remains could have turned into liquid in the process hence the bad smell. I made sure that the cleaning of the room's floor was improved by moving 'suspect furniture' to expose places that are not regularly cleaned. However, the bad smell has stuck. I developed a theory that the bad smell in my room could be coming from outside (maybe from a dead bird). I must add that the smell is not only in my room but also in two rooms that neighbor my room on opposite sides. My theory has been trashed by one of my colleagues reasoning that the smell from a dead rat is distinctive and it is the smell that is in the three rooms. I have looked out the window and around it and i don't see anything. As i continue imagining the dead rat's whereabouts another theory has emerged that it could even be more than one rat! that these rats could have eaten something poisonous and they died. But the central question still remains, where are these rats? The last theory that is costly to verify is that the rats could be located somewhere in the rooms' cabling covers. Which means that we have to unscrew and remove the covers to check. But it's very difficult to find unscrewing tools. It is now becoming very likely that i may have to put up with the smell until when it is no more. I can just hope that the bad smell 'goes' away soon. Or maybe an air freshner will work here. And what of a disinfectant. Oh, let me see how this ends ...