If the policy logs says the traffic is NAT-ed then it is not a NAT issue.
So, the intent here is to send traffic throguh VPN, but NAT the source with e0/0 interface IP?
It may fail on the other side due to proxy ID check, if the e0/0 IP is not a part of the proxy ID negotiated.
Is the enxrypted ESP packet reaching the peer in the first place?