It is unlikely, with the keeper laying on the head, that the valve isn't bent. This is especially true if the pushrod is bent.Cam was comp cams custom from previous owner so unknown. (run for 4 years)1.7 Ford rollers with perfect valve contact pattern and GT40y heads. Comp cam push rods measured to fit. But seems that the push rod is slightly bent, maybe improper shim of the rockers.
I'd run a leak down test on the cylinder that lost the valve spring assembly. My bet is it will blow air out that valve.