Biden’s interest in cutting Nord Stream 2: To assist pipelines thru Ukraine that benefit Biden natural gas.
Russian interest: Cutting off Nord Stream 2 pipelines sending energy to German manufacturing - to diminish war material output.
Various other countries interests: Cutting off Nord Stream 2 - that assists their own natural gas and energy businesses.
LOL. Instead of just shutting it down on their end, stopping to send gas through?
I'll go with your #1 as far as plausibility goes.