Hi @lsw,
It looks like your conda is up to date. Your conda-list is showing your root environment, which does seem to have a lot of things in it, but ultimately shouldn't impact your QIIME 2 installation.
Let's have you run the following to see if that helps:
conda env remove -n qiime2-2018.2
conda clean -y --all
Then follow the installation instructions again.
Also, just to cover our bases, could you provide the output from:
uname --all
(it will tell me what version if the Linux kernel you are running)