[TheMAN]

I just noticed your spark plugs being smashed... it's not from pistons hitting the spark plugs... THINK mate! if the pistons hit the spark plugs, that would be the least of your worries... you'd be looking at a new piston and new valves then!

the cause of the damage was from a broken VICS screw
you need to find out where the screw went or if it's still in bouncing around on top of the piston

then there's 4 fixes you can do:
1) replace upper intake manifold with good 2nd hand one, then replacing all screws with brand new ones from mazda using recall kit part # FSY2-13-SRZ
2) replace upper intake manifold with brand new one from mazda under specially reduced price recall part # FSY4-13-SRY
3) remove VICS completely and fill the holes... reduces low speed engine performance and lose fuel efficiency
4) find and install FS-ZE intake manifold which has a better VICS butterfly design... screws will not likely fall out due to the better VICS design... improved performance at low and high RPM extremes... the cheap inferior design of the FS-DE VICS butterflies is why the screws fall out, especially after much high RPM engine use