The evidence is available . . . he just needs the right people to testify and give evidence that children are at risk
You mean current members of the congregation? I can see that happening!
Sizemik, giving evidence in court requires evidence of an offence, not a general statement of opinion or the stories of sexual abuse in distant congregations a decade ago. The numerous docos available on YouTube are not evidence of an offence by the seven legal entities he has charged. A magistrate can't be expected to view a 30-minute television documentary and decide that an offence has thus been committed in the Traralgon congregation of Jehovah's Witnesses.
He has to prove that a minister (or elders, as he has chosen to do) worked with unrelated children, and that this is a common event, and they lacked WWC checks. For that he will need (a) the names of elders, (b) the names of children he has worked with, (c) the dates they worked together and (d) an answer to the question, "Was this an uncommon, isolated event?" If the answer is no, then he can ask them, "Do you have a current WWC check?"
If they don't, I would say the case is proven.