Well the Get Channel Followers endpoint implies you’re after users, since that’s the name of the endpoint, and the fact that the documentation for Get Channel Followers says Gets a list of users who follow a specified channel.
As for a workaround, there’s no workaround using Helix endpoints. If you want to use v5 you can continue to do so for the time being but it’s deprecated and will be removed at some point in the future.
Being able to see what games a user followers, or what users follow a game, may be included in Helix at some point in the future, or it may be a design choice to no longer support that functionality.