Cam Compression confusion

I have a Toro Titan Z that quit starting unless I manually rotate the engine off compression and then it starts fine. Numerous YouTube videos led me to a broken camshaft compression release lever failure as a probable cause. The Toro site says I have a B&S 44K777-0123-E1 and to go to the B&S website for parts. I look up the camshaft and order it from Amazon (OEM Part). I just opened the engine up and pulled the camshaft and it does not have a compression release lever at all. No broken pieces in the crankcase either. The new camshaft came in with the lever as expected. What is going on? Do some of the B&S engines release compression a different way? Do I somehow have a different engine? I bought this mower used, so I guess it's possible. The cam I pulled out is stamped 589. The new one is stamped 901. Any ideas?
 
update: the engine model number on the valve cover is a 44N677-0031-G1 which call for the the same camshaft that I ordered - 797242.