2009 Macbook not booting up
Did you reset both the SMC and PRAM (instructions is on the same support page at the Apple website)?
If you did, try it once again.

Did you try all of the things in your post with both the power adapter and on battery?

Since the machine is old and there is no support warrant left at Apple I don't think there is any idea to contact them.
Otherwise, you may have found the reason to why it was just laying around at the IT office.