The EU isn’t the United States of America, EU courts of law aren’t the United States District Court for the Northern District of California - oh, and the EU has just adopted new regulation that wasn’t applicable / in force back then.
…which, by the way, does (will, once in force) require gatekeepers to provide some access „free of charge“.
I don‘t see your point.
Epic will be able to sideload a store application.
That store application can provide downloads of third-party apps.
And downloaded apps, again, may be installed („sideloaded“).
Even if your logic with „one of either sideloading or third-party stores is enough“ were allowed (which it won’t be), Apple will retain greater control and leverage over an Epic store - than on individual apps being installed. Nuking or hampering a whole store with its dependent apps is way easier than having to act against dozens, hundreds of individual apps.
They are already doing it with the DMA. They are restricting what Apple can charge fees for:
„the gatekeeper shall allow business users and alternative providers of services provided together with, or in support of, core platform services, free of charge, effective interoperability with, and access for the purposes of interoperability to, the same operating system, hardware or software features, regardless of whether those features are part of the operating system, as are available to, or used by, that gatekeeper when providing such services.“