I had a bug that forced me to use the console with Irileth (which I'll explain in detail below). But because my load list is long I'm not sure who I should report it to, or if it is even worth reporting.
Skyrim.esm=1
Update.esm=1
Unofficial Skyrim Patch.esp=1
Dawnguard.esm=1
Unofficial Dawnguard Patch.esp=1
HearthFires.esm=1
Unofficial Hearthfire Patch.esp=1
Dragonborn.esm=1
Unofficial Dragonborn Patch.esp=1
ApachiiHair.esm=1
ETaC - RESOURCES.esm=1
EFFCore.esm=1
RSkyrimChildren.esm=1
Cutting Room Floor.esp=1
UnlimitedBookshelves.esp=1
Dragon Stalking Fix.esp=1
Darker_Caves_Dungeons_Ruins_Nights.esp=1
ETaC - Complete.esp=1
ethereal_elven_overhaul.esp=1
ETaC - Dragon Bridge South.esp=1
Guard Dialogue Overhaul.esp=1
Weapons & Armor Fixes_Remade.esp=1
Clothing & Clutter Fixes.esp=1
CollegeOfWinterholdImmersive.esp=1
Immersive Citizens - AI Overhaul.esp=1
Complete Crafting Overhaul_Remade.esp=1
Weapons & Armor_TrueWeaponsLvlLists.esp=1
Immersive Orc Strongholds.esp=1
Breezehome_Fully_Upgradable.esp=1
Immersive Weapons.esp=1
WeaponsArmorFixes_ImmersiveWeapons_Patch.esp=1
Immersive Whiterun.esp=1
Hothtrooper44_ArmorCompilation.esp=1
TheChoiceIsYours.esp=1
Cloaks.esp=1
Run For Your Lives.esp=1
Immersive Solstheim.esp=1
SMIM-Merged-All.esp=1
Immersive Patrols II.esp=1
Chesko_Frostfall.esp=1
RealisticNeedsandDiseases.esp=1
RND_HearthFires-Patch.esp=1
InvestedMagic.esp=1
CUYC_CleanUpYourCorpses.esp=1
Enchanting - IDWIW.esp=1
Better Vampires.esp=1
Blacksmith Chests.esp=1
Immersive Citizens - CRF patch.esp=1
PerkusMaximus_Master.esp=1
PerMa Expansion 1 - Wintermyst.esp=1
PerkusMaximus_Mage.esp=1
imp_helm_legend.esp=1
aMidianborn_Skyforge_Weapons.esp=1
craftable iron lockpicks.esp=1
Extended UI.esp=1
iHUD.esp=1
SKSE Hotkeys.esp=1
AHZmoreHUD.esp=1
RaceMenu.esp=1
RaceMenuPlugin.esp=1
SkyUI.esp=1
LadyKdCirclets.esp=1
Hothtrooper44_Armor_Ecksstra.esp=1
Dr_Bandolier.esp=1
LeftHandRings.esp=1
LeftHandRings - Dawnguard.esp=1
360WalkandRunPlus-RunBackwardSpeedAdjust.esp=1
wizDynamicThings.esp=1
MIDFollowMeCloser.esp=1
dD - Realistic Ragdoll Force - Realistic.esp=1
When Vampires Attack.esp=1
LootandDegradation.esp=1
RND_AnimalLoot.esp=1
RND_Dawnguard-Patch.esp=1
RND_USKP-Patch.esp=1
RND_Dragonborn-Patch.esp=1
SMDropLitTorch.esp=1
AcquisitiveSoulGemMultithreaded.esp=1
Convenient Horses.esp=1
Better Stealth AI for Followers.esp=1
PerMaDefluffedPerkDescriptions.esp=1
PerkusMaximus_Thief.esp=1
EFFDialogue.esp=1
UIExtensions.esp=1
Fast Respawn 144 Hours 1.2.esp=1
NoAnimalsReportCrimes-DG+DB.esp=1
Traps Make Noise.esp=1
WetandCold.esp=1
WetandCold - Ashes.esp=1
isilNarsil.esp=1
Hunterborn.esp=1
Hunterborn_Frostfall-Patch.esp=1
Hunterborn_RND-Patch.esp=1
My Home Is Your Home.esp=1
VL No AoE Drain.esp=1
CWIDawnDragonPatch.esp=1
CWINPCApachiiSkyHair.esp=1
PerkusMaximus_Warrior.esp=1
1nivWICCloaks.esp=1
1nivWICSkyCloaksPatch.esp=1
PerMa-Hunterborn.esp=1
PerMa_Survivalism.esp=1
PerMa_USKP master patch.esp=1
RSChildren - Complete.esp=1
RSChildren_PatchUSKP.esp=1
V740T_MGolDinS&M.esp=1
DGInvestedMagic.esp=1
Alternate Start - Live Another Life.esp=1
Bashed Patch, 0.esp=1
SOSRaceMenu.esp=1
XPMSE.esp=1
Slap.esp=1
PatchusMaximus.esp=1
I completed Bleak Falls at about level 4 and then headed off to Windhelm and Riften (Dragonstone in inventory) to focus on other things for awhile. At about level 13 I returned to White Run and activated "Dragon Rising" by giving the stone to Farengar.
The Quest (MQ104) launched successfully, I followed along with Irileth upstairs to hear the Jarl's orders. The quest advanced to the next stage (40 I believe), and me, my two followers (Faendal, Marcurio) and Irileth headed off out of the palace toward the Guard tower.
Irileth got as far as the Gildergreen tree and that is as far as she goes. When I speak to her she said something like "I'll meet you at the Watch Tower once the rest of the soldiers have gathered."
After reloading a couple times to see if anything I could do in game would fix it, same behavior on the part of that AI.
I finally circumvented it by going to the watchtower next to the White Run front gate (where the other White Run guards were assembled) and using prid 0001A67F ; moveto player ; to transport Irileth there. She immediately gave her speech and the rest of the quest progressed without problem.
I would still have save files that a mod author might use to diagnose, but I have no idea which mod(s) it might be that are causing it.