WP multi network effect on XMLRPC getPosts endpoint

How does WP Multi Network change the wp.getPosts method of XMLRPC?

I have a subdomain install with WP Multi Network running. When I send a wp.getPosts request, via CURL, targeted at a subnetwork instead of the main ‘grandmother’ network, I get the posts living on the targeted ‘mother’ site (root of the subnetwork), but NOT any posts on any daughter subsite. So I got curious, and poked around with wp.getPost instead.

When I send a wp.getPost, to a daughter site (siteID=38, with a postID=35, real username, password, URL redacted) on a subnetwork, structured like so:

curl -d '<?xml version="1.0"?> <methodCall> <methodName>wp.getPost</methodName> <params> <param> <value>38</value> </param> <param> <value>username</value> </param> <param> <value>password</value> </param> <param> <value>35</value> </param> </params> </methodCall>' http://subdomain.url.com/xmlrpc.php

…I get back the error:

<methodResponse>
  <fault>
    <value>
      <struct>
        <member>
          <name>faultCode</name>
          <value><int>404</int></value>
        </member>
        <member>
          <name>faultString</name>
          <value><string>Invalid post ID.</string></value>
        </member>
      </struct>
    </value>
  </fault>
</methodResponse>

So it seems pretty clear to me that wp.getPosts doesn’t know how to find the subsite on the subnetwork, although the IDs are proper. Any insights?

https://wordpress.org/plugins/wp-multi-network/