Polie I do not quite like the sounds of that engine . When attempting to start. Here is one thing I would do..

Now that you have the valves adjusted. Do a compression check first. Even if a cylinder is low you can still drive it and not spend dollars in speculation.

If compression is good start the simple tests. If you want a little more information post a video cranking without the glow plugs activated. Just no pre glow and turn the key to the start position will do.

I suspect uneven cranking sounds as at least one other noticed. This could also be a cylinder attempting to light off earlier but with no glow plugs used the rotation of non starting the engine should sound pretty even if the compression is. You of course could do this before the compression check.