Prior to signing with Arizona United, Yallop was said to be looking at a career as an agent. I'd say if he negotiated his new deal on his own, he's doing quite well so far. Already getting paid by the Fire for another year and has another three years guaranteed (albeit, presumably for less money). Wish I had four years of guaranteed pay for being a nice guy but not very good at my job.
It's not a severance. He had a three-year contract with the Fire and he didn't resign. He's rolling in it.
Have you seen the contract? Do you know that the Fire are required to pay the full amount of the contract if he is fired, regardless of what Yallop does next?
I haven't seen the contract and I'm quite sure you haven't either. That said, I don't know why anyone would sign one that would negate it if he was fired and got another job during the duration of the agreed upon terms. Severance is an entirely different thing.
It may be that potato agreed to a level of compensation with AZ United which would require the Fire to pay the difference between the AZ United deal and the Fire's deal for 2016. Something like that.