I was having this exact thought about one of my WIPs, too. My conclusion was that you can always have a proxy for the primary IC. In my WIP, the issue was that the end of the first Act was the MC leaving her isolated community, with the IC being in the main area with everyone else. What I can do is either a) have a character in the isolated community who expresses the IC Elements in a similar manner, or b) have the MC contemplate the IC’s world and how much different it will be. In the first case, the IC Perspective is being represented through the proxy, and in the second, by the “totem” the MC has created in their mind.
Does that make any sense?