I was discussing this elsewhere. Marshall has two manufacturing sites, Milton Keynes and Dong Nai, Viet Nam, near Ho Chi Minh city (old Saigon). Have you got any Marshall amps built in China? I figure they might subcontract some things, but it doesn't appear that they have a full manufacturing site. Marshall was sold to the Swedish Zounds group, and the Altor bought a large share of that. I think the Swedes changed things more, when they started selling headphones, bluetooth speakers and drums.
In any case, it's just another equity firm buying and selling a company, not much different from when Ford bought Jaguar, then sold it to Tata of India. They still make the Jaguars in England.
HongShan also owns large shares of Byd (EVs) ByteDance (TikTok) Genesis MedTech, Monzo (digital banking) and over a hundred other companies. It seems to be a big difference from what Ming has done building up an empire of music related companies.