Hello there Tom
Yes the original install failed which can be seen from this:
dpkg: error processing archive /var/cache/apt/archives/percona-xtradb-cluster-server-5.7_5.7.22-29.26-1.xenial_amd64.deb
(--unpack): trying to overwrite '/usr/share/man/man1/mysqlman.1.gz', which is also in package mysql-client-5.7 5.7.23-0ubuntu0.16.04.1
dpkg-deb: error: subprocess paste was killed by signal (Broken pipe)
The team here say that it looks like on that node you have the mysql-client installed, and this conflicts with Percona XtraDB Cluster. Meanwhile I will see if any of the team are free to add to this.