They’re pretty loud in general so you would probably know, but they don’t tend be like to hang about indoors. Might just be house sparrows if you’re hearing them on the warehouse floor.
You should download the Merlin ornithology app. It’s built by the Cornell ornithology lab and has picture and sound ID features for birds as well as just a lot of generally useful identification information.
Maybe stop stirring the pot? At this point it really just seems like you’re the problem here with how petty and antagonistic you’re being.