It's been a while since I've posted here

For the past few weeks we've had a girlfriend of mine living with us. Her husband deployed in Jan and she deploys in Feb so we told her to live with us for the month wait. She's awesome - cleans up after herself, helps cook etc. Recon adores her ... well at least I thought he did.
She gets home from work before us and always takes Recon on a walk. Up until last week he wouldn't poop on his walks with her. Last week he decided to poop in someone's driveway ... Odd I thought. This is the dog who will only poop in grass in my experience. Oh well I figured he maybe just really had to go.
Until last night ... She was texting me pictures of him on her bed and he looked happy. Then I got a text of a pile of poop ON HER BED! Apparently while they were laying on the bed together he stood up and went poop. I couldn't belive it!
Recon has pooped a total of three times inside our house in his life. Once when he was a baby and we were still learning his "potty signs" (our fault). And once about a year ago we came home to diahreah all over the place - poor boy was sick and you could tell he just couldn't hold it. And the third time was last night!
What would make him poop on someones' bed?? I'm wondering if he doesn't actually like her? I was shocked. She said she had just walked him and he had gone pee a few times but no poop.
I'm not sure what to make of it. Very strange for Recon.