The Skulker feat is red? Really?? You don't think negating disadvantage on Perception rolls in dim light is even worth a mention here?
TWF benefits from the increased chance to land sneak attacks and to crit with sneak attacks.
Can you tell us your methodology for crits for this table? Because that statement above does not seem possible within the rules whihc makes me question your entire table.
Yeah, I get slightly lower numbers for TWF, I'm guessing because of the crit calculation. I also get slightly higher numbers for BB starting at Level 9; I'm not sure what that's about. The bottom line still holds that TWF yields slightly higher DPR at all levels if you ignore the possibility of BB's secondary damage, significantly so in Tier 1, but by the time BB starts to scale, the gap is pretty small as a share of the average damage; small enough that IMO the combination of the control effect and being able to do something else with your bonus action is well worth it.
Example
TWF (level 5)
Main Hand (base damage): (1d6 + 4) * 0.6 = 4.5
Main Hand (crit damage) : 1d6 * 0.05 = 0.175
Off Hand (base damage) : 1d6 * 0.6 = 2.1
Off Hand (crit damage) : 1d5 * 0.05 = 0.175
Sneak Attack (base) : 3d6 * (1 - 0.4*0.4) = 8.82
Sneak Attack (crit) : 3d6 * (0.05 + 0.4 * 0.05) = 0.735
Total: = 16.51
This observation is accurate. There is a way to compute the crit chance to account for this as covered by @Esker.You can't roll both your Attack action, take your Bonus Attack action, and then determine which to apply your sneak attack. Roll your attack, if it hits decide to add SA or not, and then roll damage. There seems no way to crit hunt SA with TWF.

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.