Upon signing into this local user account (with no ties to any Microsoft account), the preinstalled Office apps notified me that a license for Office 2019 was available and could be activated by signing into a Microsoft account. The Dell tech support rep had an excellent idea to create a local account not tied to any Microsoft account. Either way, this did not fix the problem and the apps still showed no sign of an activation key. A complication to this is that I actually already had a Microsoft account under that email.
I signed out of my primary Microsoft account and into the account corresponding to the email I used during the purchase. Any Dell rep reading this, please pass this feedback along to avoid confusion in the future. There seems to be some conflicting information about how this process is handled. The documentation presented to me at the time of order suggested that the key would be emailed to me. This is a very poor policy and should be changed if true.
#Verify office key activation key
A Dell rep informed me that Dell issues the Office activation key to a Microsoft account based on the email address that I used to place the order. I was prompted to begin an Office 365 trial. When signing in to any of the preinstalled Office apps with my Microsoft account, no evidence of a valid key was presented. I was able to resolve the issue though I've been unable to confirm exactly why it was fixed: