That's precisely the point, isn't it?
"We will put an end to X" does not mean "we will physically blow up X". Pretending Biden had an "oops, we're gonna do a terrorist attack against Russian and German infrastructure and I said it out loud at a press conference!" moment and that there's no other legitimate explanation for the statement is just goofy.
The other tell is that in the follow-up, Biden was pressured to explain what he meant but he refused to comment. Sanctions could have been mentioned here without repercussions but they weren't.