I have to admit Raiklesses is not a common name I’d heard before. I was looking up the Dictionary of the Scots Language, like you do, and there it was. Two references to its use in Scotland dating to the late 19thC citing Clackmannanshire (Clc.) and Roxburghshire (Rxb.). Raikless, or reckless, is simply a corruption of auricula so not the most exciting reason for a common name.
Bear’s Ears, the translation of the old botanical latin name Auricula ursi, or garden auriculas as they are more commonly known come in all the colours of the rainbow, plus a few more on top of that. They are the result of 300+ years of selective plant breeding and are the horticultural equivalent of the fancy pigeon. With hundreds of named auricula cultivars it maybe better to describe the growers and breeders as reckless rather than the poor plant.
The Botanics has a long history of raikless cultivation, James Sutherland’s Hortus medicus Edinburgensis, or a catalogue of the plants in the Physical Garden at Edinburgh dating from 1683 lists on page 306.
Sanicula Alpina vel Auricula ursi variorum colorum, Bears-ears of divers[e] colours.
The publication predates Species Plantarum and the beginning of the binomial plant names so the names in Sutherland’s time were polynomial and a mouthful.
As I said we don’t grow many garden auriculas but we do grow the wild species Primula auricula L. and Primula hirsuta All. that are the original parents of the hybrids and led to the horticultural diversity found in all those raikless hybrids.