Update - Our QA team's findings are the following:
We confirmed unlocking Hail Rune requires Team level 101. We also confirm the level cap for server11 is set to level 100. This means when the player unlocks the new level cap and Chapter 17, Hail Rune will appear visible in the upper left. The very least, players need to reach team level 101 to make it visible in chapter16.
In conclusion, invisible Hail Rune works accurately and as intended for users in server11.
Let me know if any issues still exist with respect to our team response.