Hi there, lfking.
I appreciate you performing some tests in order to create the 2018 1099's. We can try some more steps to resolve this.
The latest released payroll update guarantees the availability of the 1099 form for 2018. You will have to update your computer date to 2019. After changing it, you should be able to run and pull the form 1099 and 1096.
Here's how to change your date to 2019:
For additional insights about 1099, please refer to this article: Set up a 1099 vendor and print forms.
That's it. Let me know if you have additional questions. I'm here to answer them all for you. Wishing you all the best!