https://www.raidisnotabackup.com/

In the US, kettles are supposedly much slower than a microwave or even a hob due to their grid.

I think that green tea bags are an exception, those’d be ruined immediately by boiling temps.

This applies to food, I doubt it’s relevant in this scenario, but I am open to being proven wrong.

Microwaves are tuned to heat water molecules.
They’ll pass right through fabric and plastic/synthetics.

The standard technique to heat non-water based things is by using a thin layer of foil (e.g. microwave Popcorn or some instant meals).
It could be a gel too, but there may be a danger if hot leak.

Unless the plushie is on fire when it’s given back to the child, I don’t see how this could go wrong.

I like my job, but even then, the ratio of work to free time is not right.