Another Interesting Home Game situation

[Snarf]

So my friends and I take poker seriously but play a 'gentleman's game' and try to be proffessional, practical and friendly about how we play...

The OFFICIAL ruling on this one is fairly obvious...but I'm curious how you 2+2ers out there in similar non-cuthroat home tourneys amongst friends handle this one:

After seeing a flop of Kd Jd 10c I push all-in on a shortish stack from the big blind. (I had Qx but that is mostly irrelevant.) A couple limpers fold around to the button. The button makes no motion for his chips, says nothing out loud and flips over his cards on the table:
(A h Q h)and THEN states - 'I flopped the straight.' I tell him that he exposed his cards and should be counted as a fold...There is some murmuring at the table...because everyone knows that while technically I am right...NO ONE at the table (or reading this) can doubt his intention to do anything other than call...but it IS technically a fold since he exposed his cards unnecessarily.

What made it especially tough is that everyone usually leaves the tough decisions up to me - and it was my tournament life on the ruling.

Everyone kinda looked at everyone not knowing what to rule...fair vs. right.

So I have two questions:
1) What would your home game rule here?
2) **IF** its a tough borderline decision...HOW would you make the official ruling. (Its usually left up to me - but my tournament life is on the line.)