Difficult. A collapse is called a collapse for a reason. You would have to prevent the Ukraine as the biggest non-Russian republic from bailing as it was at that point when even Gorbachev said that continuing the USSR would be nonsense. On the other hand, the actual threshold was the August Coup. This is when the Russian SFSR started to seize more and more power from the Union and only after that did e.g. the Baltic Republics (re-)gain serious international recognition. Yeltsin demontaged the USSR after the coup, so there was no reason to stay in the house.