Can’t fix what is broken until you do some more troubleshooting. I would start by disconnecting the speedometer cable from the right angle adapter. This should allow you to check to see if the output of the adapter is rotating, may reveal the tip of the cable drive shaft was broken by the lid - methinks that is not likely.
if the adapter spins and everything looks OK visually, you want to spin the cable driveshaft fast enough to see if the speedometer will react.
as for the electronic speedometers I know they are out there but I am still old-school. Someone else will have to chime in but just about all the major gauge companies now offer electronic GPS options
Larry