Default [Q] Sprint G2 - GSM unlock for europe - Bad ESN

Hi,

Im looking to buy a LG G2 from ebay, with the cheapest options being the bad ESN options. I am aware that the sprint G2 can be GSM unlocked (http://forum.xda-developers.com/show....php?t=2655133).

However, my question is, would i be able to buy a G2 from eBay on the Sprint network, with a bad ESN, and be able to unlock the GSM radio for international use (UK), or must the ESN be clean?

Thanks in advance (apologies if this question/similar question has been asked before)