When I worked in radar, the people in the transmitter lab had little, hand held, microwave detectors as an additional layer of safety. If a wave guide hadn't been assembled correctly and was leaking microwaves, they would be warned before they were cooked. This was 1980. Such gadgets should be very cheap today.

Given the history, with the Great Seal Bug

https://en.m.wikipedia.org/wiki/The_Thing_(listening_device)

I would expect plenty of monitoring; it is cheap and easy.