The story artist is Violeta Suarez. She did several other Schoolgirl PLs around this time, including #44 "Search in the Pyranees". Regarding the failure to nail the villains, this is a recurrent feature of girl's comic stories, where the bad guys were regularly allowed to get away with murder (sometimes almost literally). Heaven knows why, but any number of stories show that their readers preferred to see all the suffering inflicted on the heroines rather than on the malefactors.
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Schoolgirls' Picture Library 20 - Candy and Co. in Spain