I am not native English speaker, but the dictionaries are rather precise that authority is a necessary ingredient of being able to dictate something.
https://dictionary.cambridge.org/dictionary/english/dictate
"to give orders, or tell someone exactly what they must do, with total authority"
https://www.merriam-webster.com/dictionary/dictate
"to issue as an order; to impose, pronounce, or specify authoritatively"
If you don't have authority over the company you can still think you are dictating, but that's not how the company views it.
The company view is "are you too much of a problem for the benefit of keeping you?" not "John said it so we must do it because he has authority around here".