I've never seen status match so aggressively promoted! See www.bestwestern.com/en_US/best-western-rewards/status-match.html
which is clearly linked to from several places on their site.
A simple form asked me what status I was and with who, along with my name and email address and membership with BW. They didn't ask for any evidence of my HH Diamond membership, though I do have it.
Match came through in about 48 hours.