Russia doesn’t need Hungary specifically, Russia needs someone in the Eu, to destroy from inside, and give internal info and passports.
If there would be a way to kick Hungary out, most of its current support would go to some other country, nowadays Slovakia has a Russian friendly government, between 2017 and 2021 had a definitely not Russia spy as prime minister and a lot of other countries has more or less successful far right parties with russian ties. There are a lot other options, not as convenient as the Hungarian messed up captured state, but still an acceptable replacement