Joe  Plenty of criticism of the payments for Public Works activities.  The biggest loop hole is lack of documentation that materials and vendors work performed was actually received by OP. In the industry those reports are commonly called "receiving tickets".  Bold added to relevant language from the forensic report. 

pg 5 of report 

 "4. There were six dates on which the vendor issued multiple invoices, and on four of those dates the invoices issued totaled more than $5,000.
5. On one of the dates when two invoices were issued, we noted that one item on both invoices
had the same description and amount billed. We also noted other invoices where items were
billed reflecting the same description which appears on another invoice   issued within the same week. These could be duplicate billings, but without any supporting documents it is not known whether there were multiple deliveries of the same materials to support the amounts invoiced."

pg 6    " 6. No supporting documents were included with the invoices such as delivery receipts for materials signed by an employee at the site of the delivery, and daily work tickets with details as to the work performed and signed by an employee who verified the work was completed."

"7. Many of the invoices did not provide details such as the date and location of the materials delivered or work performed, and the quantity of materials delivered. " 

more  pg 6 of report "However,we noted that many of the invoices for purchases of stone, gravel and topsoil do not identify the quantity and therefore we are unable to evaluate the amounts paid to those vendors as compared to the price lists obtained."

pg 7 of report "The supporting documentation for two of the payments to that vendor consisted only of Estimates, not invoices. Payments for purchases should not be made based on Estimates."

pg 10 of report "The Finance Department should not issue payment without
support to verify the goods were received and/or services were performed"

"Public Works should require supporting documents such as delivery receipts for materials
signed by an employee at the site of delivery, and daily work tickets with details as to the work
performed and signed by an employee who verified the work was completed, and those
documents should be provided to the Finance Department along with the approved purchase
order and vendor invoice. "

I believe there are some individuals who were rooting for an OPA employee to be complicit in the missing bank deposits. 

Nonsense, unsupported speculation.  

Tom