The 'Johnsons' left the building before Grzegorz and his two guests even managed to approach you. Either they were late for the daily coprorate anthem singing competition, or the negotiations didn't go as they planned.
Uncle Good Advice pulls out a small, but clean rag, and polishes his horns, as he answers your questions.
"Well, this is a job I've got through unusual channels. Somebody pulled a lot of strings to get me on this. And I don't really know who's the original employer. I've managed to find out the first middleman. He's a scum. But we can screw him over. I have my contacts overseas, and between you and me, I'm sure we'll find the buyer." He pauses, and lets his female companion squeze through, as she prepares to leave. "Mariana was here because of the negotiations. She would know all about the job anyway, because of her ties, and she had a present for your comrade here." He points at Vabka. "Though the Vory don't have much respect here, for obvious reasons, she and her boss have a new way of doing business. New for the Vory, that is. We have a mutual understanding, but she won't interfere with your job." He pauses fo a moment, to finish cleaning his horns, and recieve a goodbye peck on the cheek from Mariana, who nods, and gives you a quick "До свидания", and blows Vabka a kiss, as she leaves the bar. "What a woman. Ekhm... Were was I? Oh. The job. So, a while ago I've hired a bunch of kids to find something that was lost since the first war. It was part of a stolen archeological museum display. An urn, or something like that. And they did find it, but their mage told me it was magical. I figured as much, but I've been paid, so I pay those kids, with a hefty bonus for being honets, and turn the thing over to Mr. Johnson. He downs another shot of Vodka, this time a Russian brand. "Somebody made a mess, slaughtered the Johnson, and his two bodyguards - standard corporate goons, so no trouble here. And the thing vanished. We managed to pull some strings, and hire a good expert on things magical, and he told us that vase is still here, in TriCity. And then the offer came. Somebody wants to pay you over 25 thousand nuyen each to get it, and kill the mastermind behind the heist. If you don't find him, you still get the whole sum. But if you do, there will be a nice material bonus included. You can make a wish - that's what the employer said." He stops, and looks at you, smiling half to himself...
Side note: As soon as the troll Fixer started talking, all of your commlinks displayed a 'NO SIGNAL' warning. And Yani experienced a sudden impulse Jammer burst, that with his ECCM didn't even startled him. All he managed to find out before was there are signs of Resonance tampering that look almost like a sprite's, except there's no trace of any owner signature.