Hilti HIT-HY 270 - CMU Connection

We are reviewing a connection of a steel relieving angle support bracket to a fully-grouted CMU wall. The bracket is fastened to the wall with Hilti HAS rods with the Hilti HIT-HY 270 system. Per the Product Technical Guide and ICC-ES ESR-4143, the holes in the bracket should have been 1/16" larger than the rod diameter as is standard for bearing connections. Due to a detailing error, the bracket was fabricated with vertical slotted holes (slotted in the load direction), and this discrepancy was not identified until after the brackets were installed. Based on some torque testing, the engineer is taking the position that the 5 ft-pounds of installation torque will inhibit slippage of the connection in the slotted hole and will allow the connectors to develop adequate capacity. Is there anything that would justify this design approach? Could the sustained tension in the anchor result in any minor creep over time that could allow for slippage in the connection?

Thank you for your assistance.

Best regards,

Tom