Agree, the entire complaint is fascinating reading. I suspect Deel's responses will mostly be "we deny everything," but any counter-arguments they make will also be very interesting.

I have to say, I think if this was just limited to the Slack previewing behavior, it's unlikely it would have been caught. Previewing Slack channels is not particularly unusual or suspicious behavior and many people, probably most, don't even think of it as being something that'd be logged. (I personally didn't think of it until reading this post, but in retrospect, of course it is. Everything is.)

Crossing the line into dumb things like Deel executives personally contacting the spy's subordinates via their personal phone numbers, which he had no way of knowing is like sending up a massive flare of weirdness. I'm not saying loyalty to one's employer is everything, or even particularly important, but if I was randomly headhunted by a C-level from a direct competitor, who I had never spoken to or expressed interest in, I'd be pretty suspicious, and I'd find it underhanded. I might mention it to someone.

Supposing the allegations are substantially true, I wonder why Deel felt comfortable going that far. Maybe underestimation of competition?