Looks like you are running EWC,  have you tried using the internal  DHCP server on the WLC and see if that works.  The AP and EWC is directly connected.  

@Mark Elsen  is correct, you would need some log and a bit more information to start looking at what may have gone wrong.The 2 WLC's that failed, can we assume they were in SSO, what was the state of SSO when you check?

We are running Version 17.9.3.. at this exact moment, I was drafting and email to Vocera support to see what I would need to enable to get some good logs for what going with the badges during a multicast session. We get reports of great days and some...

Are you using Vocera? we had a complete outage with our multicast, and after  about 5 days of TAC, we rebooted the WLC and everything been working since, that was in Dec/2023.. We would see the UP/UP in show multicast mom on the AP, and then they wou...