The Marsden Isotopy

The target is Benjamin Lacasse, one of the palace staff members working in the ground-floor kitchen by the bar.

To acquire a Tech Crew disguise, you can start wearing one by choosing the undercover in the AV Centre starting location (Mastery Level 7), or you can obtain one by vaulting the gate to the south-east of the palace perimeter, then continuing straight until you get to a flood light generator. Turn it off to lure a tech crewman over, then pacify him, hide his body behind a wall and take his disguise.

There are a few kitchen knives in the kitchen, but they are illegal to carry in the Tech Crew disguise, so you will need to wait until both palace staff members have their backs turned, then quickly pick one up and perform a silent melee kill on Lacasse. At this point, quickly drag him to the other side of the table he was working out to temporarily hide him from the other person in the room, then once her back is turned again hide Lacasse in a nearby empty closet.

Since there is a place to hide Lacasse's body right next to him, this complication shouldn't change much.

The new target is Philip Von Zell, Viktor Novikov's personal assistant who talks to him about the Shadow Client and Valerie St. Clair. He starts in the corridor by the Great Hall on the west-side of the ground-floor palace in a phone call, then goes through the kitchen and behind the bar to wait for Novikov.

If you are quick enough, you can intercept Von Zell before he makes it to the kitchen by throwing a coin into the bathroom farthest from the palace staff member on his phone as Von Zell walks by it. Alternatively, you can lure him into the top-right corner of the kitchen as he enters it to kill him and hide him in the same closet as Lacasse. Finally, if he does make it to behind the bar, sneak behind him, garrote him and hide him in the closet next to the palace staff member chopping limes. If you are struggling to do this without said staff seeing you, you may need to pacify him and hide him in the closet as well before Von Zell arrives.

Although quite the spectacle, this complication doesn't add much to the contract.

You have more than likely already completed level 3 or 4 in less than 5 minutes anyway, so this new complication also doesn't add to the contract much.