Dramatis Personae

"Roll a D6 for each searcher. If any of the searchers rolls under his Initiative he has located the special character."

Is this correct, or is it 'equal to or under' as pr. usual I tests?

It's a bit odd, but I'd go with the rules as written - you have to roll under, not equal to or under.

It's quite possible it's a mistake and it was intended to be a normal Initiative test, but it's impossible to say for sure - so I'd just go with exactly how it is written.