OptiPlex 3060 BIOS

Chances are the Windows 11 license (which the installer picked up when you went online) belongs to the company that owned the system.  You can purchase a new license key from Microsoft and use it to activate the Windows -- that will remove the company's license information from the system.  This is a Windows issue - not a firmware issue.

Is it just the bios logo?

https://www.dell.com/community/en/conversations/optiplex-desktops/revert-to-the-default-dell-bios-splash-screen-from-a-custom-logo/694fcf4e04bdbe791572ad64?keyword=Logo

Re: I performed a low level format on the SSD

Did OP wipe the ssd clean? Format only clears one partition and does not affect other hidden partition.

i would use MS installation media to delete all the partitions on ssd then try clean install Windows 11 again 

@ejn63​ 

The Win installation media USB drive was created on another machine.  The problem is I can't progress beyond the login page that requires a company e-mail address.

@redxps630​ 

No, I get the Dell logo on boot up.  Its when the machine finishes the Win 11 install it wants an e-mail address from the company that previously owned the machine.

@Matthew Turner​ 

That's because it's activating the license key that belongs to the corporate owner of the system.  Unless you can get them to deactivate it with Microsoft, you will need a new license key of your own.

Prepare your Windows 11 installation USB driveusing the Microsoft Media Creation Tool or by extracting the ISO file to a USB drive.

Navigate to the sources folder on your USB installation drive.

Create a new text file inside the sources folder.

Name the file ei.cfg (make sure file extensions are visible in File Explorer so it's not named ei.cfg.txt).

Open the ei.cfg file with a text editor (like Notepad) and add the following text

[Channel] 

@redxps630​ OK I'll give that a try and let you know how I get on.  Thanks

@redxps630​ Just tried that and got the same result with the corporate login screen at the end of the installation.

have you already tried deleting all partitions on the ssd before clean install.

your experience appears to report the issue is not due to a bios product key but a setting on ssd that still has company info. 
you may try a test ssd or hdd that you own that has nothing to do with the pc, remove the original ssd, install the test ssd/hdd in Optiplex then install Windows 11.  just to see if that issue goes away.

@redxps630​ Yes, I performed a low level format before starting the installation.

@Alex307​ Yes, this is a fresh download of Win 11 with a total clean SSD 

Re: When the OS install completed I was presented with a login screen from the company

this is not expected for normal Win 11 install.  Normal install prompts you to name the pc then asks to choose MS account vs school/work. You would have to choose one option.  OP did not report any of these steps.  OP did not explain how the install was completed without these prompt screens.

something is off.  

If no further report of how Win 11 was installed I would cut the knot by removing ssd from this pc do a clean Win 11 install on it using another pc.  Set up normal local account vs MS account log in. Then move ssd back to 3060.