Does he need a 2nd account?
I thought that this worked because Hyatt status expires in February and mLife expires in October. So as soon as one expires, you match from the one that has not expired.
So... you are Explorist through Feb 2020. There is no point doing anything yet.
In Oct 2019, you status match to mLife. Now you have mLife status which will not expire until the end of Sept 2020.
When your Hyatt status expires in Feb 2020, you status match from mLife. Now you have Explorist until Feb 2021.
You repeat this every October (when mLife expires) and February (when WoH expires)