The exchange is not taking the other side of the bet; they're just matching you up with another user who wants to take the opposite position to you and then taking a fee for providing that service.
Did you contact Anker? Among the many products I've bought from them, I've had a couple of problematic ones, but have found that in these cases their support has been very helpful and sent me a replacement, even a year or so after the original purchase.
I'm pretty sure that when you register a Homebridge instance to your Apple device though you get a message about the accessory being in test mode.
Homebridge is presumably making use of some debug mode that you wouldn't use in a shipping product - and if you did, Apple wouldn't let you advertise it as officially compatible with HomeKit.
I think that the "if-then" part is a simplification of imperative paradigms.
I've never heard it described that way, but I assume the part about "pin pointed procedures" tied to data is a weird way of describing the way that methods relate to the data encapsulated by their owning object.
Ultimately, I think this is a case where someone familiar with the concept has explained it to someone who is not, who has then tried to paraphrase and, lacking any domain knowledge, summarised it in an unusual and vague way.
Don't most large organisations require something similar with their own open source projects? I know Google and Facebook do.
It's just a way of confirming that you own the rights to your contribution, and that you explicitly give Microsoft permission to use it. (And if you didn't want to grant them permission, you would have no reason to contribute!)