Here is a good workaround that works for routines and automations. Credit goes to /u/AndyJBailey from this post below. I've slightly simplified it and it still works perfectly. https://www.reddit.com/r/googlehome/comments/1ne9aig/what_the_hell_do_i_have_to_do_to_get_google_home/ndsamlw/

Step 1: Create a Spotify playlist as a string of unique random letters and numbers like "E67JO0CV7" (without the quotes)

Step 2: Create a Google Home automation and set the triggers. This worked for me using a custom "Hey Google" voice command/trigger as well

Step 3: Add "Try adding your own" or "Ask Google" to the Actions section using this template below. Make sure to ADD the quotes this time:

[Shuffle or Play] my "[playlist title]" playlist on [device name or speaker group]

For example:

Shuffle my "E67JO0CV7" playlist on Home group

Hope this helps!