You guys are making me nuts about this SOL.
It does not mean they can't file, and they'll probably get sanctioned if they do. It means they won't get a judgement.
But and this is a big BUT, if they do file, you must take action. The court does not have a clue that this is outside SOL unless you mention it.
You think they're going to bring it up? No! So yes, they can still get a judgement if you don't defend it.
Of course you can have the judgement vacated at a later date but why would you want to go through that.
Don't sit on your laurels about SOL. If they file, you must respond.