They mention an "arrest affidavit." I didn't know what that was, it apparently is a report that the arresting officer files. Based on the article, it looks like a number of people went to the police to file charges, and the affidavit lists the accusations in order to present a cause for the arrest. I fear this will not end well for the victims.
My guess is that they'll look for anything they can charge him with, but he probably will not be charged with most of the crimes and may be acquitted of any that he is charged with. These are very tough cases to prosecute- there is probably little or no physical evidence, and witness testimony in such cases (that occurred many years prior) can be very inconsistent and easy to attack in cross-examination.
It is a reminder of how damaging the WTS's policies and actions have been over the decades. You have to wonder how many men like this are out there, who will essentially get away with serial rape for many years, aided by misguided policies and people unprepared to deal with the issue and unwilling to seek help.