The status of this item is changed from 'unplanned' to 'wont'fix'. When AllowParsingWithountSeparator is True parsing is 1:1 like military parsing and to be successful in both directions (click date in calendar builds date in military format and edit text produces proper date) user needs to set short date and short time format via custom culture. This is explained in military parsing help article. We will make sure to update the documentation regarding the supported formats when using AllowParsingWithoutSeparator true.
https://docs.telerik.com/devtools/wpf/controls/raddatetimepicker/features/militaryparsing