DNA tests (according to Lebanese sources) done on Saja Al-Duleimi (the woman that was caught on the Lebanese border) and the 3 children that were traveling with her did prove that she is an ex-wife of Al-Baghdadi, and she's the same woman identified by the Iraqi intelligence (whose brother is detained in Baghdad for terrorist activities in Basra, sister is detained in Kurdistan after failing to execute a suicide attack in Erbil, and her father is a leader in Al-Nusra Front in Syria), although she isn't one of Al-Baghdadi's current (3?) wives.
The Lebanese authorities explained that she was married three times. The first husband was a member of Saddam's regime and she had two sons from him, and then married Al-Baghdadi for a brief period (for 3 months about 6 years ago) and had a daughter from him (which was reportedly proved by DNA), and now she's married to a Palestinian man and she's pregnant from him.
Worth mentioning is that she was a part of the exchange that freed the Ma'loula nuns months ago, and it seems that more information about her surfaced after her release in that exchange (she was already detained for terrorist activities but her relationship to Al-Baghdadi wasn't known at the time).
Besides Saja Al-Duleimi, the Lebanese forces also caught the wife of another senior Al-Nusra leader (his name is Anas Sharkas and is also known as Abu Ali Al-Shishani), but they didn't give much information about her apart from her name being Alaa.