After reading the details in the article below, I had a flash of insight. Thank you, Almighty God. Read through the article (short) until you reach the part where "Blinken repeated Joe Biden's threat that the USA will impose additional, SWIFT and severe costs on Russia for going ahead with the referendums". Emphasis mine.
So - could the Nord Stream pipeline sabotage be the "swift" retribution that the Biden Administration promised? It sure looks like it. The referendum voting began on September 23rd. By September 26th (Monday) it was being reported that the voting was going well - all in Russia's favour. The Nord Stream pipeline was sabotaged on Tuesday September 27th. Well, well, well! And if I can put two and two together - so can the European politicians. There is going to be a lot of fall-out over this.