Can I use Verizon iPhone 4 on US Cellular?

My sister-in-law gave my kids her two old iPhone 4's. They were Verizon phones and we use US Cellular. I was optimistic to use them in this new age of phone sharing. The phone tech told me that they are both CDMA, both 1800MHz, but the Verizon is 2-band and US Cellular uses 4 bands so it is not compatible. Am I being given correct information? It smells like a weak story to coerce me into buying their product.

Correction: both carriers are 800 and 1900MHz (not 1800MHz I mentioned above).