One janitor and two maintenance men took the gopher into a small janitorial closet and apparently decided to kill it. No other reason for spraying cleaning solvent on the gopher seems plausible.
The solvent was designed to remove gum from surfaces. It freezes the surface gum and makes it easier to scrape it up. Elementary schools have an unsurprising need for such solvents. But the gopher was stronger than the gum. Three cans later, it was still alive and kicking.
They paused for thought, and the janitor, who was most badly injured, attempted to light a cigarette in the fume-filled room. The subsequent explosion injured the three men, and sixteen children were treated for scraped knees.
In the aftermath of the explosion, the persecuted gopher was discovered unharmed and clinging to a wall. He was released back into the wild, where he is expected to enjoy years of free drinks in gopher pubs as he tells the story of his brush with death.