Roy Johnson’s technique, used only for the skipping part, produces the desired result:

$name =~ s{
    (?<!C(?=.O)) # doesn't match C-something-O starting at previous ch
+aracter
    (?<!\d)      # not preceeded by digits
    (?:\\|\/)    # back or forward slash
    (?!\d)       # not succeeded by digits
}
{ & }xg;        # replace with '&' (globally)
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Makeshifts last the longest.