Warning: Spoilers for 'Critical Mass', and also it only makes much more sense if you've seen it.
Note: This was done quickly and posted immediately; please forgive any idiotic mistakes. Thank you.
Rodney wasn't a coward. Alright, fine; yes,he used to be, but the definition of 'used to be' means 'in the past'. Because it is. He isn't a coward anymore. That is completely not the reason that he is hiding in one of the extra supplies room hidden behind a couple of stacks of rations with his laptop. Not at all. He just wanted some peace and quiet and this just happened to be the best place for it. Of course. The fact that Cadman was extraordinarily creepy - she had been inside him - and searching for him had nothing to do with it. Peace and quiet.
But, why was she searching for him? That made absolutely no sense at all. Unless of course she was coming to confront him on being suspicious of her being the Trust operative. She had walked in on the little 'meeting' when he'd been insisting that it could be her. No, that still didn't make sense. It'd been days since then, and she would've confronted him earlier about it. She was that blunt, frank type of person. So then why on God's green Earth - well, more like blue Atlantis - was she stalking him, because he swore she was.
He had been innocently going to the lunchroom; there she was, so he took a detour, did some other stuff, went back in twenty minutes. She was still there. Fine. He goes to the science lab; she appears in five minutes. He returns to the cafeteria, eats, leaves, and sees her entering from the other entrance. He goes to find Sheppard. She's already talking to him!
'I'm going insane. There is no possible way that Cadman is stalking me-'
"Hey Rodney," Cadman said casually while walking past him.
He yelped. "Where did you come from?"
She gave him a strange look and said slowly, "From the hallway.."
"Oh. Well, don't sneak up on people like that!" He huffed at her before hastily retreating.
It was at this point that he had retreated to the storage room. But Rodney McKay is not a coward. Stop thinking that, because he's not. Really. And just because he stayed there until he was forced to come out because Elizabeth wanted to have a group meeting, he's not a coward. And so what if he sat opposite of Cadman and refused to look at her? He wasn't attracted to her. Why should he have to look at her if he wasn't attracted to her? Alright, so she was a blonde, but that didn't mean anything. Just because he tried to run away after the meeting - even though he failed - he wasn't a coward. Really.
"Oh god, I'm such a coward," he moaned. "Coward, coward, coward, coward.."