Was this RCD damaged by overcurrent?

Chris of YouTube channel CJR Electrical attended a fault where an RCD/GFCI was tripping regularly. He found that the placement of the circuits in the consumer unit (domestic distribution board) was potentially resulting in a lot of current through the RCD/GFCI and wondered if it had suffered internal damage.
Here's a link to Chris's original video where he discusses the issue:-
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Tracing rogue tripping of RCD/GFCI breakers can be difficult at times, as the fault current is low and can be transient. It usually involves water heating or cooking equipment and can sometimes resolve itself when stuff dries out.
Chris replaced the RCD/GFCI with a new one designed to detect AC and pulsing DC faults associated with faulty electronic equipment, and it appears to have solved the problem.

In this video I test and then strip down the original breaker to see if it's showing signs of thermal damage. The passive tripping circuitry is very delicate and relies on a latch being maintained in position by a low level magnetic force, and being released by current being induced in a coil so it snaps open and fires the trip mechanism. The circuit board is just two inverse parallel diodes to clamp the maximum voltage from the sense coil, and some capacitors in series with the trip coil for fine tuning.

I wonder if this arrangement is prone to being affected by external vibration or magnetic fields, and how that changes with time.

Note that the current rating on these RCD/GFCI breakers is purely their rated current handling capacity. They do not have overcurrent sensing. They can only trip when detecting current imbalance through leakage.

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