That is a poor description of the ventilation requirements. Perhaps if you look at the underneath you can distinguish where the air flows in and where it flows out of the assembly. Not much air is going to be rising as in their diagram if it can't go out of the cabinet somehow.

And for air to go into the kick panel area, that would have to be a grill, and not a panel.

What I did for my Electrolux/Kenmore/Frigidaire induction cooktop is have a fully open cabinet interior (no panel below the cooktop) and used wire shelving holding pots and pans. I haven't yet detected any significant heating of the interior volume. I had intended to use a small rack blower to refresh the cabinet air, but never installed it because it seemed unnecessary in practice.

Thz for your comments.

Since the cooktop is a sealed glass plate on the counter top there is no possibility that it will aid ventilation.

we will have the RAS wire pot rack in the cavity below - so there not much else i could do to allow air flow within the space that way.

I've been considering something similar to your ideas about active ventilation using PC fans, but feel the proper implementation to make it automatic will be needlessly complicating the installation... and that would require creating intake / outlet anyway... so i might as well provide those vents for passive venting first, and i can later supplement with active venting if temperatures are unacceptable.

What I meant was to examine the bottom. There are slots there. Does the air flow in or out of the slots? If it flows in, where does it flow out? Or vice versa?

the cooktop has ventilation slots and a 'heat deflector' detailed in the manual.

none of that addresses the provision of unheated air into the cabinet though - or it's exhaust from the cabinet.

the closed cabinet is effectively a sealed unit, albeit with some leakage around the door... but none out the top where the heat will concentrate

Maybe switch to another induction cooktop. Example: GE Profile PHP9030DTBB: