Packer vmware-iso builder failing with "unexpected EOF" - vmware

Question

I am new to Packer and have been attempting to use the Packer vmware-iso builder. I have attempted to build both an Ubuntu 18.04 and a CentOS 7 template. Both are failing at the same point. I am unsure what I'm missing.
I'm not even sure where to begin troubleshooting.
When I run packer build it proceeds through the following steps:
Retrieving ISO
Leaving retrieve loop for ISO
Creating floppy disk... (I am using a floppy disk for the .cfg file because I'm building directly on the esx host)
Uploading Floppy to remote machine...
Uploading ISO to remote machine...
Creating required virtual machine disks
Building and writing VMX file
Build 'ubuntu-1604' errored: unexpected EOF
Some builds didn't complete successfully and had errors:
ubuntu-1604: unexpected EOF
Builds finished but no artifacts were created
This doesn't seem accurate as artifacts are present on the ESX host:
packer_cache folder with ISO
virtual machine folder with a vmdk file, but no vmx files are present.
Here is some of the log output:
2019/04/19 12:03:30 packer: 2019/04/19 12:03:30 Writing VMX to: /tmp/vmw-iso942565597/ubuntu-1804-base.vmx
2019/04/19 12:03:30 packer: 2019/04/19 12:03:30 Cleaning up remote path: /vmfs/volumes/datastore1/packer_cache/packer670624036
2019/04/19 12:03:30 packer: 2019/04/19 12:03:30 Removing remote cache path /vmfs/volumes/datastore1/packer_cache/packer670624036 (local /vmfs/volumes/datastore1/packer_cache/packer670624036)
2019/04/19 12:03:30 packer: 2019/04/19 12:03:30 [DEBUG] Opening new ssh session
2019/04/19 12:03:30 packer: 2019/04/19 12:03:30 [DEBUG] starting remote command: rm -f "/vmfs/volumes/datastore1/packer_cache/packer670624036"
2019/04/19 12:03:30 packer: 2019/04/19 12:03:30 Deleting floppy disk: /tmp/packer670624036
2019/04/19 12:03:30 packer: panic: runtime error: invalid memory address or nil pointer dereference
2019/04/19 12:03:30 packer: [signal SIGSEGV: segmentation violation code=0x1 addr=0x10 pc=0x1df735c]