Even your link does not say what you say. It says US secretary of state James Baker told Gorbachev NATO forces would not move east from Germany. Then it goes

Even your link does not say what you say. It says US secretary of state James Baker told Gorbachev NATO forces would not move east from Germany. Then it goes into that there is a lack of formal, legal enforcement of these promises, and how the US changed its mind later. So even this source with its leanings does not say what you say.