just saw your weqatal note. i think your own instrincts are in the right
direction.
you need to add two more views:
5. veqatal = and he was in process of locking (the locks) . . .
(equivalent tense-aspect to yiqtol).
(this occurs elsewhere, 2 Sam 13.18)
here: multiple event, more than one lock on plural doors,
providing a pause as scene switches.
6. veqatal = veqatol (infinitive absolute, like phoenician. but we don't
really know enough about how this qatol functioned in narrative to
satisfyingly introduce it here.)
i prefer #5, though #1/2 and #6 are not impossible.
[another rule of thumb: always interpret the MT as one edition of the
text, even if secondary.]
[your own translation 'locker' overlaps with #5, though you may have overly
restricted the 'reading' of the TAM to a nominalization 'locker'.]