I noticed in the video that one dog kept looking up to the shelf above him. My guess is that it was fairly easy to get down from that shelf but not to get back up it.
Your firefighter definitely deserves the title "Hero!" Going up to a strange dog in a rough situation where he might get a lot more than he bargained for is rough call. Glad it worked out right for all concerned.
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“Properly trained, a man can be dog’s best friend.”
Corey Ford