This is the method I use in your scenario, OP. You can use Folder2iso to get the files in that you need. If the OS has official VMware tools, you can also mount the VMware Tools ISO straight from workstation into the VM and this will give you the clipboard service so you can copy and paste files between the host and VM, if this scenario is permitted within your isolation needs.
Otherwise, go the ISO route. You just can't bring stuff out of the VM back to the host is all.
The two aren't even in the same league. I'm a big open source advocate don't get me wrong, but VirtualBox is horrible to use and its not what OP asked.
If you're not trying to create complex virtual networks, or have hardware accelerated graphics, VirtualBox can be a bit unintuitive, but has all of the features that VMWare makes you pay for, available for free.
I don't use VMware, so these are just ideas. Without using a network, I have to possible solutions in mind: a) can you drag and drop between the machines? or b) use a usb-stick to write and read from, at least until you find a better solution.
Not sure whether open-vm-tools is needed for that, but you could try using the clipboard for the purpose. Compress the data and BASE32 encode it. Maybe also split it to smaller units so that it fits any clipboard limits.
How much data do you want to transfer?
You could also consider copying open-vm-tools to the VM this way, and then you could make use of proper shared folders.