Close? Sure. But remember what they say, close only counts in horse shoes and hand grenades. How close is close? Is crossing at 68 close enough? What about crossing at 69? either one would be "close", but they would also represent a big value drop. So is it close enough for you? (disclaimer, a lot of PCGS and NGC 70's if cracked out a resummitted raw would probably be found to be "close" as well.)
I have crossed ICG coins to Pcgs at same grade. However the market prefers PCGS / NGC. Any slabbed coin - Ymmv.
I've done a lot of business with ICG, PCGS and NGC. ICG did make some mistakes stretching grades beyond what the coin merited. But these days they are right on the money, very accurate. I have had coins upgrade substantially from ICG to NGC. I've had ICG and Anacs coins cross over or go up or down a notch at PCGS. Check out The Coin Geek's videos on Youtube. It looks like ICG will over push coins they like, but others will crossover at the same grade.