Support
It's commonplace for normal accounts on OSRS obtain their lower-tiered clue scrolls via impling jars, so I don't have an issue with that being the case here as well, so long as the cost reflects the convenience.
It's much less common for players to grind elite clues through Dragon impling jars due to the high cost, so those should be left out. Also, as you mentioned above, elites are most commonly received from late to end-game PVM, so that should remain the meta to incentivize players to do that content.
Based on current OSRS prices, these are the rough costs for clues through impling jars. These should be considered and adjusted for the Alora economy if this suggestion were to be implemented.
Gourmet: 1/25 rate for easy clues
On average, one would profit −12,257.00 to get an easy clue scroll from gourmet impling jars at current Grand Exchange prices, excluding the rewards from the completed Treasure Trails.
Eclectic: 1/25 rate for medium clues
On average, one would profit −35,029.50 to get a medium clue scroll from eclectic impling jars at current Grand Exchange prices, excluding the rewards from the completed Treasure Trails.
Ninja: 1/25 rate for hard clues
On average, one would profit −571,053.00 to get a hard clue scroll from ninja impling jars at current Grand Exchange prices, excluding the rewards from the completed Treasure Trails.
Dragon: 1/50 rate for elite clues
On average, one would profit −12,661,194 coins to get an elite clue scroll from dragon impling jars at current Grand Exchange prices, excluding the rewards from the completed Treasure Trails.