I am in a similar situation. It does not feel safe for big companies to rely on one man shows or small companies. Are there any ways for small companies to get out of this?

Ask some founders or do some research on how B2B companies got started. My n=1 experience working for a startup is that the founders were well connected and got one big contract from a health care system and expanded from there.

They also got investment from their customer and their customer opened doors.