In the 6 to 8 weeks it probably takes to implement you can use this user script:
// ==UserScript==
// @name Show Timeout in Chat for mods and RO's
// @namespace http://stackoverflow.com/users/578411/rene
// @version 0.1
// @description show a timeout message for RO's and mods
// @author rene
// @match *://chat.stackoverflow.com/rooms/*
// @match *://chat.stackexchange.com/rooms/*
// @match *://chat.meta.stackexchange.com/rooms/*
// @grant none
// ==/UserScript==
(function() {
'use strict';
var MS = 10000, // 10 seconds
cb=$('#chat-buttons'),
todiv = $('<div></div>'),
timer,
room = /.+\/rooms\/(\d+)/.exec(window.location.href)[1];
cb.append(todiv);
todiv.hide();
function giantS(num, text) {
return num === 1 ? text : text + 's';
}
// poll ....
timer = setInterval(function() {
// post to events, we need one record
$.post('/chats/' + room + '/events',
{
fkey: $("input[name='fkey']").attr("value"),
mode: 'Messages',
since: 0,
msgCount: 1
},
function (data) {
// yes, the root object either has a timeout property, or not
if (data.timeout) {
todiv.text('Timeout ' + data.timeout + giantS(data.timeout,' second') + ' remaining');
todiv.show();
} else {
todiv.hide();
}
});
}, MS);
})();
The script polls the /events
endpoint every 10 seconds to see if there is a timeout specified.
When the script is active in a room and a timeout is set this is what an RO, Mod or CM will see:

If you have TamperMonkey(Chrome) or GreaseMonkey(FF) installed you can easy install the script from the SOCVR Userscripts GitHub repository.