The way that I have done this in the past is by showing repeatable impact to our bottom line. First, I recommend setting up a process to ensure you are diligent in reporting and have accurate attribution in place. Then you can start testing out the different levers as you look for repeatable pipeline impact. I suggest working closely with your cross-functional counterparts such as BD, product, and sales to ensure you are all working on the same initiatives to see an outsized impact.
It is critical to have full buy-in from the exec team on the role partnerships play in the company's growth. They should believe in the potential of partner marketing to amplify the partnership's awareness, adoption, and revenue impact. The best way to get buy-in is by making progress and showing traction. There is no better reasoning than evidence to invest further into what is working. I would run with any creative hacks to drive your KPIs and rather ask for forgiveness, not permission to test your hypotheses. Your customers are your strongest marketing assets. Can you find 1-2 customers who will back up your initiatives and represent your voice to the executive team?