Qadha of qasr salaah;paying someone with fake money unintentionally

if while on a holiday one is a musaafir required to read qasr salaah but one does not, in the event of making qadha when one returns home is the full salaah read or the qasr salaah?

there is a special place for parking in town where one has to pay R5 for the parking. during one of my rare visits i parked in the area and paid the attendant. on arriving home i realized that the R2 coin with which i paid was a fake. i dont ever go there so what should i do now? give it in sadaqah?