You are looking for Hot Fix 5 (HF5) for Aria Operations for Logs
The files you have downloaded do not work.
You still can’t find the HF5 for download for the version(8.18.3) you are on.
When you try to install the HF5 patch file, you get the error "Failed to upgrade. PAK file format error."
Aria Operations for Logs 8.18.3
The pak file downloaded was for the Aria Operations product, not Aria Operations for Logs.
There is no Hot Fix 5 for Aria Operations for Logs 8.18.3.