Yes. u-boot accesses the SD card, loads the next stage of booting (Linux & the Endless initramfs) into RAM, and executes it. The Endless logo appears on-screen.
The emergency mode failure at this point usually indicates that Linux cannot access the main filesystem for some reason.
Many components are involved in the bootup process, to know where to look in the source code we really need to understand the failure first, and I think UART console is the most realistic way forward there.
However, if I am to guess, you are seeing the same issue that prevents us booting on Raspberry Pi 400. We have not tested yet, but this could likely be fixed by either one of the following u-boot code changes.
https://lists.denx.de/pipermail/u-boot/2021-September/462006.html
https://patchwork.ozlabs.org/project/uboot/patch/20210822143656.289891-1-sjoerd@collabora.com/