Need Integration key for CRM Integration (Trial Account)

Hello, I am interested in purchasing a business subscription for Adobe sign to incorporate with my company's Microsoft Dynamics CRM 2016 on premise environment, however, I need to provide at least a proof of concept utilizing the trial version before I can get purchase approval. I've already installed the solution in CRM, however, next steps require an "integration key" for Adobe Sign. The problem is that it doesn't seem like I can retrieve this integration key through the Adobe Sign portal. Can I please get assistance with this?