As already noted, you want to eliminate any potential issues pertaining to external hardware, and a monitor is external hardware for any headless computer.
I think the question should be do you have another monitor you could try with to rule it in/out?
I do want to know is anyone else running automations that they don’t want user interaction for?
Hello @bocciaman 
Regardless of what issues might still persist as of today and the fact that Power Manager has an annual subscription model …
it’s packed with a lot of features for automation
it is the only kind of software that is able to unlock your Mac for doing what it is supposed to do (what is actually one of the best features of all this Application has to offer). Because of this feature you can let all your Macs do what ever they are set up to do without your interaction and you are able to keep your Mac security as high as possible….
while pmset has great options for waking up your Mac and all the other things you can do with it - it is not able to log you automatically into your User Account…
Every thing that could be done without visual dependency is possible if you’re able to script it and combine it with launchagents and or Keyboard Maestro, Automator, EventScripts or other automation tools.
But when it comes to automations which use images as a base you would have to be logged into your account… maybe you can create something that is able to detect when your Mac is not at sleep anymore and logging you in … but this will cost you parts of your Mac‘s security… and here comes another great feature to play if you have PowerManager … it is even able to lock you in when your Mac was booted up from shutdown and manage your automations. I don’t know if that is even possible without PowerManager. Maybe not…
Greetings from Germany
Tobias
It also has a non-subscription option:
Hello @MevetS
Thanks for reminding me on the existence of this article… I totally forgot about that this exists…
Greetings from Germany
Tobias