Cold crashing them will stop the carb process, or at least slow it way down.
Were the tester bottles warm when you opened them? That is partly the problem, if yes. I would try to cold crash them, then pop the caps, release some pressure, and recap them.
"Beer, well respected and rightly consumed, can be a gift of God. It is one of his mysteries, which it was his delight to conceal and the glory of kings to search out."
The Search for God and Guinness by Stephen Mansfield