Nowhere on this coin does it suggest passing to either player would make it offside. Indeed, I think the most reasonable interpretation is that it's saying that if you passed to one player it would be offside while passing to the other player wouldn't be.
In other words, the coin got it right! To quote the designer of the coin:
With all due respect, I reject Mal Davies's interpretation of the coin (rather than his interpretation of the offside law). Nowhere on the coin does it say that the 'offside' player is committing an offence – that is a supposition entirely of Mal's creation.
The coin simply states that the player is 'offside' – which is true, irrespective of whether or not an 'offside offence' results from this scenario. Furthermore, there are clearly space limitations on the coinface so it was obviously impossible to go into the finer details of the offside rule.
I think this incident highlights an important point. If you're going to mouth off about something, it's first a good thing to check that it's not you who has misinterpreted the information at hand. A simple rule of thumb to follow is that if there's a charitable and uncharitable way of interpreting what was said, it's probably best to give the benefit of the doubt and take the charitable option.