First, join the discord server as the problem statement says. Now we look for channels that look like anouncement channels, because if it was posted in one of the chat channels it would probably get buried. (We're assuming that the organizers aren't evil.) 
We find the channels `#announcements`, `#update` (in the CTF section), and `#updates` (in the LIT section). Let's look through the channels. `#updates` is just a bunch of old messages from 2021, and `#update` doesn't contain any interesting info either. 
But if we scroll up in the `#announcements` channel, we find a [message](https://discord.com/channels/738848412912451695/738863205048123403/999912370921033778) with the flag, which is `LITCTF{L1T_1S_G0NNA_BE_S0_LIT_W1TH_Y0U_GUYS!}` (which turned out to be true).