Hello, javablood.
Welcome to Microsoft Community!
For the Surface Laptop 5 stuck in the Welcome state, you should have tried a forced reboot:
Force a shutdown and restart your Surface - Microsoft Support

If a forced reboot still doesn't help you boot the device properly, the only thing we can do right now is to see if we can access the UEFI settings:
How to use Surface UEFI - Microsoft Support
If we have access to the UEFI, then in fact we have a chance to format the device. In the case of not being able to boot the device this may be the only thing we can still do:
Creating and using a USB recovery drive for Surface - Microsoft Support
Honestly, I didn't want it to come to this. Because formatting will eventually cause you to lose all your local backups.
The above is what we can try on our own. If you still want more help, I can share with you the steps to get in touch with the Surface Support team.
You can refer to the following steps to create a service order for hardware services when you cannot power on the computer:
- Use your personal Microsoft account (not your organization account) to access the following links:
Contact - Microsoft Support
- Type Surface won't start, press Enter, and click "Contact Support" at the bottom:

- Select Technical Support and select the device model (Surface Laptop) you are currently using in Product family, then click Confirm:

- You will see contact options for Chat support and Phone support, please contact them during business hours:

I wish you all the best.
Best Regards.
Leo.L - Microsoft Community Support Specialist