As @mike.maxwell mentioned, sending a "delay" to a ZigBee device as a singular HubAction command makes no sense, there's no such device command as delay.
A delay is supposed to be used within a sequence of commands, so for ZigBee like:
"zdo bind ZZZZZZ, delay AAA, he cr YYYYY"
delay is just a marker to signal to HE to delay sending the next command by AAA ms, it doesn't actually get sent to the device.
I've not looked fully at your code, but IMO it would make more sense to use HubMultiAction:
https://docs.hubitat.com/index.php?title=HubMultiAction_Object
allActions.add(new hubitat.device.HubMultiAction(cmds,
hubitat.device.Protocol.ZIGBEE))
But it depends on what you do with "allActions" ..... for example if that just gets passed to sendHubCommand then I'd just do:
sendHubCommand(new hubitat.device.HubMultiAction(cmds, hubitat.device.Protocol.ZIGBEE))
i.e. just pass your raw cmds list (assuming it's a List of Strings) and let HE figure the rest out 
