Lifetime radios in a car are non-transferable. The CSR would have to waive the restriction. You're best bet is to claim your radio was stolen. Even then, transfer is 100% at their discression.
Good luck. And if another opportunity presents itself, don't do a lifetime on an OEM radio.
I've never heard of such a restriction where is this restriction shown in writing in the TOS or Lifetime subs description?
But I do agree with the others, I would never call and say I have a such and such and want to switch to such and such. I just tell them, I'd like to do a Radio Swap, they ask what is the ESN on the radio you want to swap due to the fact that your radio has died and you've been unable to find a replacement, then you give them that ESN, then they ask you the ESN of the new radio and that is that. I understand it is a bit different with Lifetime subs, but again I'd tell them it died and that you've been unable to find a replacement so you just want to switch the sub to another radio. If you tell them it was stolen they may want a police report. So, I would avoid that all together!
If you read the lifetime fine print it clearly says OEM lifetime subs are non-transferable except (at their discression) in the event of theft, damage, etc.