Some experience talking here.

Burkerts need more than 24V to control CO2 pressure.
Some do the job on 24V , others won't even budge on 30V.
That is why Burkert sells a valve rated @ 50 bar that can withstand 200bar. It's the control issue.
That could explain the non working valve. Feed it 36V and see that it does.

The one that seems open all the time. Or the seal on the rim leaks, or the seal on the lower edge is damaged.
I would be surprised if the spring is cracked and not powerfull enough to close the plunjer like it should.