Log: https://paste.ee/p/zVzFQ

I have tried adding a few custom emotes to my client to test out before adding to a server, and the emotes have been working fine however when open the emotes tab in chat (pictured), I get the black/pink missing texture instead of my custom ones or even the "unknown" texture that I thought Quark had. The images are in the config/quark_emotes folder as the YouTube tutorial showed, and are 16x16 PNG files. The emotes also do not have keybinds added for them (although I don't know if this is intended or not), so can only be used from chat.
I have tried this with and without Optifine, but to no avail.
Quark version is 3.2-358 due to modpack limitations, and I understand that this is unlikely to be an issue on the mod's end, but if anyone has experienced this problem or something similar and found a solution please share as it has been quite a headache.

Picture-

quark_emotes file (contains the images + .emote files) -
quark_emotes.zip