The trick is that McDonald's has not left Russia, but has transferred its assets to a shell owner. “This guy” doesn't even bother to abide by the terms of the agreement, according to which he has no right to use the original McDonald's menu and the original recipe. When this is all over, McDonald's will get its business back in Russia without any problems. The terms of the deal give McDonald's a priority right to buy back its business for 15 years.
Yes, the solution I would suggest is very tough, but very effective. Firing 60,000 employees in Russia and closing 850 restaurants would cause a huge scandal here, showing the effectiveness of sanctions and the inability of the government to solve the problem. Instead, McDonald's turned the business over to a Russian oligarch, formerly associated with Roman Abramovich, who is now on the sanctions list himself.