委托 and 悬赏 — the work that is not in the quest log

Commissions and bounties are not quests. They live in EntrustGlobalManager and XuanShangManager, each with its own state, which is why the game's tracker gives them tabs of their own and why nothing that walks the quest log will ever find them.

Where a commission comes from

A letter announcing one is an announcement, not the thing itself. The offer lives on the character, and you open it by talking to them and taking 委托. What happens then runs in this order (EntrustManager.OnNpcChatEntrust):

1. Already holding one from them? They repeat their "not done yet" line. Nothing else happens. This is the most common reason a promised commission looks like it does not exist.
2. At the cap? Twenty active commissions across all characters, and they decline.
3. Nothing queued? Slots refresh on timers; the one the letter announced may have rolled over.
4. Otherwise you get it.

Where it points

Both systems answer GetZhiYingTargetPos — the same resolver the tracker's arrow uses. It is worth using rather than a stored coordinate, because a commission's target wanders: the resolver asks where they are now. Where it declines to answer, the person who gave you the work is the sane destination, since that is where the errand ends.

Why side quests often have no arrow either

A quest condition only resolves to a position for the handful of types the game guides: talk to, follow, kill / protect / win, and go-to-position (ConditionPrototype.GetTargetPos). Everything else — fetch six of these, learn that skill, wait three days — returns zero, which the game reports as 该任务无法被指引.

Those conditions still carry a source position: the spot the quest hangs off, usually the giver or the place the step belongs to. It is not the objective, but it is a far better answer than none, and it is what the trainer falls back to.