Very little experience for completing Levelling roulette

Date & Time: July 19, ~13:35
Frequency: Happened at least once before but I have not done the content a lot
World name: Sargatanas
Character name: Athral Stark
Class/Level: Paladin, Lvl 97
Party or solo: Random party
In-game time: N/A
Area and coordinates: Great Gubal Library, normal/story mode (came up during roulette)
Steps:
1. Queue for levelling roulette, Tank role is available for bonus experience
2. Finish levelling roulette
3. At level 97 on Paladin, I gained 159.832 experience points after the final boss (and an additional bonus of 136.080 for playing a sought-after role). I assume this is ONLY the experience from the dungeon itself as the standard chat message for completing roulette content did not appear.
For comparison: I gained 849.636 experience for completing a trial roulette just minutes before and the standard message appeared here. I had NOT done a levelling roulette during this reset period before (in fact, I had not done a levelling roulette in over a week before this).