Although you did not specifically say in your post that you did not take the laptops, only expressing concern over possibly being accused of taking them, for the sake of argument I am going to assume you did not take the laptops.

With that said, I want to address the following statement you made:

"Packed up my stuff and went down to security. My husband signed out we had a brief hello and goodbye with security and left for the night. "

Here are my questions

1. Is there any way to leave the building and the security guard not see you?

2. Since the security guard saw you leave when you signed out and said hello, would he have seen you carrying anything that would appear to be a laptop? Or was your husband carrying anything that would appear to be a laptop?

The first question is very important. If there is another way to leave the building without a face-to-face meeting with the security guard, then there is your reasonable doubt on someone being able to prove you took them.  However not only can this show that someone else took them, but it also provides you with a way to have stolen them yourself, so tread lightly when this issue arises in conversation (if it ever does).

From my limited law experience (only about 50 million episodes of Law & Order), I do not believe fingerprints are enough to meet the burden of proof to be guilty of theft. You had a reasonable reason for your prints to be on that desk, so that would mitigate them being there. Additionally, if no one (the security guard or otherwise) ever saw you with the laptops, then you couldn't have stolen them. But, if there is another way to leave the building and not see the security guard, then I don't know what to say.

Regardless, I wouldn't be suprised if a polygraph was used to help determine who took them. I personally would not recommend you take a poly, but this will leave you open to unfortunate looks of being guilty, as well as a reason to fire you. 

I would not agree to a poly until you consult a lawyer. But I would seriously think about the answers to the questions I posed earlier, and the implications of them on the appearance of you being guilty. 

Randy