Can you link to the server/messages on Discord? We would need to see them and verify them.
But in general, for stuff happening outside of the P&W Discord Server, we have no ability to moderate the content. That falls upon the owners/moderators of that server, along with Discord's Trust & Safety Team.
The issue is the alliance is using broken image links, and they need to correct their alliance description. So it's not an issue on your end, it's an issue with how they set up their description.