Question Can any MATX motherboard fit in any ATX case

Are the stand offs the score things?
I have no idea what a 'score thing' is.

The standoffs are the spacers that screw into the bottom divider wall of the case and to which the motherboard is then screwed into through its mounting holes. Some cases come from the mfr. with no standoffs installed at all and some come with them all installed.

One of the more common build errors happens when people fail to remove an unused standoff, or don't put them all in. The motherboard then shorts out to either an unused standoff or the case bottom. Also, the force required to insert parts (GPU, memory DIMM's, 24pin power connector, the CPU heatsink, etc.) will bend the board quite a bit if it's not fully supported with the stand-offs which can crack a solder joint, again resulting in unreliable operation.