Slack failing at XMPP

1.xml

<!-- Trying to list the rooms. It only shows general, even though I'm in at least one more room. -->

<iq type="get" to="conference.[team].xmpp.slack.com" id="ab52a">
<query xmlns="http://jabber.org/protocol/disco#items"/>
</iq>

<iq from="conference.[team].xmpp.slack.com" type="result" to="[user]@[team].xmpp.slack.com/bucket" id="ab52a">
<query xmlns="http://jabber.org/protocol/disco#items">
<item name="general" jid="general@conference.[team].xmpp.slack.com"/>
</query>
</iq>

2.xml

<!-- Trying to get the capabilities of General so that I can join it. It fails. :/ -->

<iq type="get" to="general@conference.[team].xmpp.slack.com" id="ab53a">
<query xmlns="http://jabber.org/protocol/disco#info"/>
</iq>

<iq from="general@conference.[team].xmpp.slack.com" type="error" id="ab53a">
<error type="cancel">
<service-unavailable xmlns="urn:ietf:params:xml:ns:xmpp-stanzas"/>
<text xmlns="urn:ietf:params:xml:ns:xmpp-stanzas" xml:lang="en">Unrecognized request</text>
</error>
</iq>