Is working for a big corporation invariably wrong livelihood?

That can be a very complicated point. Almost every work for a big corporation could be (potentially) seen as wrong livelihood! Hard to find a big corporation that works with good products, ethical conduct, respects the environment, the employees and is not involved in tax evasion, bribe or any other scandal... so what is more important from a Buddhist's point of view: What YOU do in your work routine or what your company does or sells?