PM is a Private Message. If you click on the user name, you will get various options. If the person is a Gold Member (paying membership on the Forum - and well worth it in my opinion) then you will have the option of sending either an email or a private message.
You can click on my user name and try it. But I'm not sure if you will have the PM option or email option because you are currently the a registered user - I think you've got to join the forums as a minimum Gold Membership to get those privileges. If you ever intend to sell on here, it's required that you be a Gold Member at least. From a buying standpoint - especially for those of us who collect multiple knives, it pays for itself in the communication privileges.
The key to understanding what happened is this: Normally there are certain times that things happen. Andy opens his sale thread at 3pm on Fridays. Chris opens his Thursday evenings. Allen offers a few knives on Wednesday evenings. Check their respective forums for details (Osprey Knives and W.A. Surls).
But...during shows like this Kansas City show, or the big Blade Show in Atlanta, they will sometimes also offer knives via Instagram.
The first person (based on the timestamp) who claims something is the winner. I once had a knife that I claimed via PM, and another forum member (Warrior108) claimed via the forum thread, literally a few moments apart. My claim was not visible to him, so he thought he won the blade. When Allen explained that I had sent a PM earlier, he immediately deferred to my claim.
Just our forum etiquette. And now we (Warrior108) look out for each other on here constantly! I still owe him a drink!
One other thing. Allen is very responsive to hearing what people want. If you really want a bog oak Huntsman, keep checking every Wednesday. It wouldn't surprise me if in the next month or two one showed up for sale on his Wednesday thread. I have won a few knives I wanted this way - it just requires patience...sometimes it just takes a while before one pops up... and some speed and luck when the thread opens.
T