Fortunately it was the left latch, as I could insert a longish thin screwdriver and push the lever to release it. I bodged a fix which should work until a new cable assy get here. While I was at it, I decided to bend a coat hook to see if I could pull on the right hand latch to release it if I should ever need to. This worked, but I didn't realize the warning switch lives there and I dislodged it by accident. It's all back together now.
It will probably be good information for someone down the road to know you don't need to take anything apart to open the hood when the cable fails. A long thin screwdriver to push the left or a bent coat hook to pull the right latch, but be careful of the switch. From the front grille go through the hole where the black latch cable runs.
The above is for LH drive, but I suspect RH drive would be the same.