An update for anyone who might follow this. Based on the questions and feedback so far, I managed to turn the engine backward and forward through a rotation of just under 360 degrees of the crank shaft. It appears as if all the valves move properly and the ones on cylinders 2 & 3 are up when it stops. I pulled off the sump yesterday and everything looks good from underneath. I confirmed that pistons 2 & 3 are up, but stop shy of TDC in both directions.
It looks like the next step is to remove the head and see if I can find anything there. When I looked at the pictures of the front cover and the timing chain, I didn't see an easy way to account for an obstruction at 360 degrees of rotation. Thanks for the feedback so far, and hopefully I will get a chance to lift the head over the weekend.