原译文没问题。如果要表达你说的意思，要说escaped through an underground tunnel/passage等。

我给你看几个外刊例句体会一下，以帮助你理解：

1.They are concerned that perhaps they have escaped underground, but we have no knowledge of tunnels, caves, or bomb shelters to hold such numbers.

2. Many of us escaped underground, and hid here. 

3. The palace was burnt to the ground, but the wise Pandava brothers escaped through an underground tunnel.