Not being able to browse to the metric is expected because by now the agent has been removed from the Investigator due to not being connected anymore.
I let mine run overnight and saw the same thing you did.
Only way I could see to lift the clamp was to have an agent connect back and then either trim the metrics or raise the clamp level.
Basically the clamp won't be lifted until the # of metrics is reduced below the clamp level or the clamp level is raised.
Double check with Product Management on if this is how the design is. I believe it is but get confirmation.
Thanks,
Matt