For the record I have just tried the code from the docs in an ssh session and it returns
<?xml version="1.0" encoding="utf-8"?><d:error xmlns:d=“DAV:” xmlns:s=“sabre/dav”>
<s:exception>Sabre\DAV\Exception\NotFound</s:exception>
<s:message>File not found: trash-bin in ‘root’</s:message>
</d:error>
So it looks like something isn’t working right anyway.
(there are definitely files that have been deleted for the user I am testing with and the Web interface shows them correctly.)