Navigating larger companies

I'm still lost as to how to navigate larger companies. Larger companies do sponsor visas and have a lot of alums there. However, the challenges are the following

1. Too many Business Units
2. Too many alums
3. Too many positions

To navigate this maze, I need to find one person who will forward my resume for as many positions I find. However, this was possible only in the company I interned with. I found an alum who is a real sweetheart in terms of helping others. He helped me find my internship by referring me. For full time too he referred me up to almost 20 positions so far in all kinds of roles (analyst, manager, sales, etc). These kind of people are so hard to find.

So this should be my strategy going forward.

1. For each company I will reach out to at least 5 people, so that even if one person is busy I can quickly fall back on the other people.
2. Also for each company I will reach out to at least 5 recruiters, so that the recruiter who is hiring for the role knows I exist. 
3. Identify latest positions. This is a pain in the wrong place for many of the positions because they don't have the options to sort by date. 
4. Tailor resume and submit.