You're right.There's nothing wrong with the company.
The thing is that in case of brexit service sector is thought to be hit hard by slowing British economy.At least for some time.
Lack of big institutions among shareholders also doesn't help.
Don't remember the ipo price,was it 164p? It's not far off that level so it's very tempting to buy in.
I don't think that people will vote to leave EU and even if they do Kainos is present in other European countries and US which should help to mitigate the hit.
I sold KNOS some time ago but only because I saw better opportunity somewhere else and now having some spare cash (wish I had more really) gonna buy some here in the coming days. Hopefully it won't rise much by then.