Slack in timing chain after replacement

I replaced the timing chain, upper and lower fixed guides, tensioner guide, tensioner bolt, and the intake camshaft phaser. And when I turn the engine over it had still had slack in the chain. I was told it was fine, so I put everything back together. And started the engine. It still ran poorly, and I was informed that it probably had a bent valve.

So, I pulled of the cylinder head. And it seemed that a couple of the valves were not seating correctly.

I took the head to a very reputable second generation machine shop in town.

I was informed two days later that the head was done, when I got there the gentleman told me that none of the valves were bent. He said that there was so much carbon on the valves that they were not seating. And told me to use an oil catch can to prevent that.

I put the head back on, using new a new head gasket and head bolts. When I got the timing lined up, there was slack on it even after I released the timing bolt. (I will attach a video of me turning the engine over.)

I'm currently putting the intake and exhaust manifolds on. But I will not be starting the engine until I figure out the tension problem.