Incorrect. Trump wanted the National Guard there ...
Since he could have brought them there in minutes with a simple phone call, but did not do so, clearly he did NOT want them there.
and ultimately delegated the use of the National Guard to the Defense Secretary
All modern presidents including Trump have delegated deployment of the DC national guard to the Secretary of Defense who delegates it to the Secretary of the Army, this is standard procedure and has nothing to do with this particular event. The President is still at the top of the command tree and could have ordered the guard in at any time, like as soon as the first barricade was overrun especially since he knew the mob was armed sufficiently to not be able to get through metal detectors.
The protestors ended up taking a tour of of a largely empty Capitol building ...
If it was just "a tour" why was congress evacuated? Why was Pence's security detail calling their families and telling them that they loved them clearly thinking that they might die in the next few minutes?