A No Witness (or One Witness) Trial?

Hi folks!

Here is another question about Deuteronomy 22:

In Deuteronomy 22:23-27, there are laws about rape. If a man rapes a betrothed woman in town, both the man and the woman are executed, since the woman could have cried to others for help but did not do so. If a man rapes a betrothed woman in an open field, however, then only the man is executed, since the rape occurred in a field where there was no one to help her.

How can this be reconciled with Deuteronomy 17:6 and 19:15, which says that a matter must be established at the mouth of two or three witnesses before a defendant is executed? If there was no one in the open field to help the woman, then presumably there were not two other people there who witnessed the rape. While Deuteronomy 17:6 relates to apostacy cases, 19:15 appears to be broader in scope, since it appears in a chapter about homicide, manslaughter, and landmark cases, and it also says that two or more witnesses are needed to establish guilt regarding all sin and iniquity. In the case of rape in the open field, is the case basically decided on the basis of the woman's word against the man?