It seems none of them, coz the match wasn't played.
"The Bronze
Following Estonia's decision to forfeit the match, Spain assumed their lineup would no longer be needed and it's players became "unavailable". Due to them being unable to find players to replenish the team, they no option but to forfeit also. As it was in fact Estonia's decision to not play that forced Spain into losing their lineup, this makes both nations equally as responsible. Added to this, the deadline for this NationsCup has now arrived so no more postponing is possible. It is for this reason that a bronze cup will not be handed to either Spain or Estonia. While both teams were clearly deserving of the title, we just cant push this NC on any more."
vs 
"The Bronze
Following Estonia's decision to forfeit the match, Spain assumed their lineup would no longer be needed and it's players became "unavailable". Due to them being unable to find players to replenish the team, they no option but to forfeit also. As it was in fact Estonia's decision to not play that forced Spain into losing their lineup, this makes both nations equally as responsible. Added to this, the deadline for this NationsCup has now arrived so no more postponing is possible. It is for this reason that a bronze cup will not be handed to either Spain or Estonia. While both teams were clearly deserving of the title, we just cant push this NC on any more."
Source: http://clanbase.ggl.com/news_league.php?nid=165064&lid=1746