Overriding BIOS 8 Beep Code

Boss gave me a Dell XPS14Z that was dropped, LCD was almost torn off, lid badly damaged, but it ran with an external monitor. Boss wanted to use it with only the external, so I (foolishly) removed the LCD and cover to use with the external monitor like a keyboard, but now get the 8-beep BIOS alert.  How can I override the BIOS without a monitor so I can boot up directly to the external monitor? Any suggestions are greatly appreciated. Help me keep my job ☺