Would have made sense that only Attack Titan users come to help, as they are the only one to resist the founder titan's power.
There's some theory out there that Eren is not even there, but back in Paradise Island. Like he controls the founder titan like the War Hammer titan. Now that Zeke is dead he can fall back on Historia's baby to control the founder titan again. It's a really nice theory that makes use what author shown us and such 10k IQ plan lol.