I've answered to a quite similar request on this forum, please have a look, but long story short:
AWS Import/export tool works if EC2 instance was initially converted from VMware to AWS. Other way to do it is the tool you mention, I've heard we can also convert from AMI to vSphere.
Otherwise, you need to reinstall your app into VMware, since this is a tricky process to convert from EC2.
Thanks much for your response.
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