"On 6 March, Homendy also said the NTSB has “engaged our attorneys” because Spirit failed to disclose that technicians who performed the rivet rework were not employed by Spirit, but rather by three other firms. Those others were engineering services provider AeroTec, aerospace staffing firm Strom Aviation, and “Launch”, also an apparent staffing firm."
Probably Aerotek, a nation wide staffing firm, not AeroTec.
There is an AeroTEC (Aerospace Testing Engineering & Certification Inc.) that does engineering support in Washington state, but it doesn't look like they supply riveters.
I wonder if the contract with Spirit precluded contract employees on the assembly line. It does make some sense for Spirit to use contract workers as the contract workers likely live in the area so Spirit would not have to move them from Tulsa or go through the hiring process and manage so much that goes with out-of-state employees.
That this is getting to the point the NTSB is preparing to fire photon torpedoes at Spirit is a sad situation for aerospace. This is not a situation where a crash site has 1000s of tiny fragments and nothing to go on. Everything about the incident itself is rather well known. What isn't known is how it started so that future, similar starts can be avoided. Someone removed the door/plug; someone put it back. It's best to understand why they did it and why it was done incompletely.
Spirit should know who did these tasks and those people need to be interviewed by NTSB.
"“Boeing has not provided us with the documents and information that we have requested numerous times over the past few months, specifically with respect to opening, closing and removal of the door [plug], and the team that does that work at the Renton facility,” NTSB chair Jennifer Homendy told US lawmakers on 6 March."
"She says a Boeing team of 25 people and a manager in Renton oversee 737 doors."
Which seems right, but this isn't one of the doors that Boeing appears to deal with so Boeing would not have information about opening, closing, and removal at Renton if their team does not do that work. Seems simple enough to confirm that is the case and tie off that thread for the NTSB and continue into Spirit.
A possible reason both are clammed up is that the riveters from one of the contracting agencies asked a favor from a worker at Boeing to help get the door out of the way. No work-order, no procedure, and the Boeing worker isn't a door guy. This would expose both companies for having off-procedure work being done and would not have triggered an inspection of the re-install because, per the records, no work had been done. At some point another Spirit worker noted the damaged seal and got and installed a replacement with a work order, but this is when they would find no removal work order for the door/plug, so they couldn't generate an install work order.