If LLDP is off on the ICXs, we will likely forward/flood LLDP like any other packet. If LLDP is on (lldp run globally), we will trap it to the cpu and it will not be forwarded. Do you have LLDP on for the two ICXs?
Ben Beck, RCNA, Principal Technical Support Engineer support.ruckuswireless.com/contact-us
HP includes the output of "show cdp neighbors" in LLDP, and vice-versa. That looks like a CDP result, which the ICX switches are likely forwarding as they do not process it. You could try disabling CDP TX on the 4500's port to confirm.