Steve,
I can’t guarantee this would work, but I might try using something like using Wireshark to grab a packet over a WIFI network then copying the payload into our software. Just make sure you are copying the FCS field as well.
If possible, an alternative might be to disable the FCS check (or ignore it), transmit a known payload and verify the payload at the receiver manually looking for bit errors. If you transmitted all 0’s/1’s it would be easy to verify.
Andrew