1994 Suzuki Sidekick gas tank dented in accident

My daughter was rear-ended, not much visible damage. But when we took it to get it checked out, they said the gas tank was dented. They want to replace it with a reconditioned tank and I am unsure about this. I am not sure where this tank is coming from, what if it has stuff in it. They assured me, it was fine, however, it's to their benefit, so... Also is dangerous to drive around with a dented tank? Should I insist on a new tank? Thanks, for our help.
Julene Waters