Many Tahm mains (myself included) have suggested a compromise for this issue, as riot has previously stated they don't want Tahm eating red/blue buff.
Instead of having Kench be able to devour the buffs, at least let him stack his passive on the baddies.
That way Tahm still wouldn't be able to devour them, but can gain the Q stun and extra damage on autos, helping him out a bit on the buffs.
Even so, this 'buff' isn't entirely needed, as his E passive/shield and devour are incredibly powerful against camps like krugs or raptors, and having a small weakness like this helps balance out his strong jungling.
Either way though, a change like this would be nice.