The Tomb of the Burning Heart can be done solo - just use Halt Undead to make the ghouls stand on the pressure plates.
The Tomb of the Shadow Lord just needs a hireling for pulling levers.
The Tomb of the Tormented just needs a hireling for pulling levers.
The Xorian Cypher just needs a hireling for pulling a lever.
Any quest with a pressure plate will allow you to use an immobile mob for it.
I used to think that too - the last time I posted in a thread about needing one live person to pass the gear back and forth, I was schooled
Turns out, you can unlock the lever without pulling it. Leave your hireling there, then run to the other side. Target their lever and instruct them to use, then pull yours. Easy as pie. Just clear out your side, and call them to you. Eventually, the gates to their side will open so you can clear it out to continue down the hall.