Just to add, as I may have already stated previously, the front panel fitting would be for a specific type of case that would not fit in any other type of PC case, as is much the same with front panels not being compliant as a general housing for all PC cases. The PC case for that front panel would be specific to the manufacturer of the motherboard, a proprietory fitting so unless an agreement with other motherboard manufacturers was in force, it would be in use only with ASROCK.
You may note the type of front panel housing in different PC cases, they are very rarely able to be fitted in other makes or models of other PC cases that is why the PC cases come with the front panel pre-fitted, it's the only hardware you basically get with a new PC case.