Tabouti is one of the key players here. She tried to quit midway through the tour, but the Palace begged her not to do so until she returned, and, out of courtesy to them, Tabouti grinned and bore it till the end of the tour, quitting immediately upon returning.
The Palace issued a glowing press release praising her skills, talent, and performance of her duties, but studiously ignoring the issue of WHY and MEGHAN.
Tabouti was Meghan's P.A. on the tour. P.A.s are on call and on hand nearly 24/7, especially on tours. It isn't feasible that Tabouti didn't witness the teacup throwing incident at Admiralty House, or at least be the first person to receive the complaint.
The word was that Meghan was outraged that she didn't have the entire Admiralty House as accommodation, rather than "just" a suite within it.
It was also leaked that she screamed at Harry incessantly, and that after the teacup throwing incident Harry went in to Meghan, closed the door, and begged her to change her behaviour AND also brought up her stupidity in announcing her pregnancy at Eugenie's wedding as she did.
The fact is, there are a great many people out there who saw too much and know too much, and by setting herself up as a martyr to justify bailing but wanting to keep a foot in the royal door (although it's clear she's now given up on that), Meghan has unwarily left one flank exposed.
As Honest Abe put it, You can fool some of the people all the time, and all the people some of the time, but you can't fool all the people all the time.
Meghan has forgotten this, and the people she couldn't fool didn't just disappear.
With Tabouti's name mentioned increasingly, as is the name Admiralty House, it's a matter of time before the people on hand start spilling the beans.