I was messaged by and responded to both. I suspect they're different people.

I also am not sure they're scams in the traditional sense. An employer match is the sort of thing that encourages this sort of thinking:

Whether or not this is within the letter of a match policy depends on the specific policy, but it's typically against the spirit and recommended against by Double the Donation. So even if there is no lurking chargeback, I would caution against this as burning the commons for short-term gain.

Also, if you have a strange story, keep Robin Hanson's recent Facebook post in mind:

If someone ever wants to give me $1M+ out of the blue, I hope they'll do more than send me an email w/o phone number I could call to confirm

Keeping that in mind, so far hans_jonsson seems legit. (I've only put a moderate amount of effort into verifying his claims.)