How do I remove the activation lock without the original owners info

You can't.

If you can't reach the previous owner whose ID is on the device and have them go to https://www.icloud.com/find/, erase the device, then remove it from their account, then the device is useless. Apple won't unlock it.

Turn off Activation Lock - Apple Support.  *

Contact Apple. 

How to request access to a deceased family member's Apple accounts - Apple Support.    *

Apple ID - Official Apple Support.   -

Contact Apple for help with Apple ID account security - Apple Support.  *  (Link doesn’t always load)   

Get Support    -  Work through the screens to get a chat option. 

Apple Support schedule phone call.  -

Apple on Twitter-  

Messages chat with Apple