I just looked up the lore for spectators and I hadn't realized what Good Boys they were.
Originally Posted by https://forgottenrealms.fandom.com/wiki/Spectator
Spectators were vigilant and trustworthy, and could be relied upon to protect items in all but the most dire situations.
...
The greatest pleasure for most spectators was thwarting the forces of chaos and in defending valuable objects. A spectator's strong sense of justice dictated that creatures who did not intrude upon their duties had a right to live, and they would never attack a helpless opponent unless attacked via sly or cruel means. Killing creatures for any reason outside of duty or self-defense would lead most spectators to commit suicide in distress via self-imposed brain overload.
Somewhat mild and even-tempered, they were even known to form friendships with other creatures, a trait that no other beholderkin or true beholder ever displayed.
...
Spectators were peaceful and would never attack unless seriously provoked. When not guarding something, if they were attacked by any opponent powerful enough to harm them, they would typically flee. Spectators only willingly fought against those who disturbed what they were guarding, those who persistently pestered them and other spectators. The methods used to repel foes would become more drastic as the battle continued, starting with fear and confusion and escalating into paralysis and enervation.
So yeah that Spectator we encounter shouldn't even attack us, at least not without us attacking it first. And what is it even guarding there? Obviously not the Drow.