There are very few things that Microsoft won't pass the buck on in a VMware environment, so I don't usually take those arguments too seriously.
However, Bitlocker only effectively works with a TPM, which is a hardware device, and I have never seen a method of passing that through to a VM. So no, you won't be able to use Bitlocker in a VM.
Are you sure this is a HIPAA requirement? I have never reviewed those requirements myself, but I have numerous medical clients and I've always told by them not to bother worrying about this sort of thing.