Jim entered the building right as he saw the insane man jump through the window. The building wasn't burning that much at his current location, but the smoke was definitely settling in. 
 "Hello? Anyoneeee?" Jim heard as he walked, ever so slowly, partly due to his seemingly broken back, and partly for stealth. 
[i] There's someone here! It might be Spencer! [/i] 
"Spencer!" Jim yelled as he ran towards her voice, even as the pain pulsed through his back. Soon enough, he found Spencer, and without saying anything, he grabbed her hand and pulled her towards the exit. 
"Move quick. We need to get out of here. The fire's growing." Jim said as soon as he saw her realize what was happening. When they got out of the school, Jim saw the other survivor, the one he saved from the madman move towards a wooded area. Jim then led Spencer to that same place, trying to catch the attention of the survivor.