Getting into new large organisations is a challenge.
They have gatekeepers to keep people like you from meeting with them.
You cannot blame companies for doing this. If their senior executives accepted every invitation to meet with a potential vendor, they would never get their own work done!
One suggestion was “View their Author Page” which means see who is writing all the interesting articles on the Company Blog. Find a way to connect with them via common interests (shared problems in the same industry, innovation or other topics), then use that relationship to be introduced to important stakeholders within the organisation.
Chances are, someone who has been trusted to write about the Company’s vision is already an important stakeholder. Their support could help you to build a great relationship with that organisation.
I have not tried this idea myself. But I will give it a try myself.