I am seeking confirmation on the following:

Part 1.

A DB plan offers a disability benefit to a participant who
has not yet attained NRA. This benefit is "auxiliary" meaning
the receipt of the disability payments do not affect the participant's
right to his vested, accrued benefit at NRA. In other words, the
normal retirement benefit will be the same regardless of
whether he received a disability benefit or not.

As an auxiliary benefit, my understanding is that the
plan is not required to make payment in the form
of a QJSA. The spouse of the disabled participant is
protected by the QPSA rules. Is this correct?

Part 2.
(Same facts as above except that participant is single when he
becomes disabled.)
If a single participant marries while receiving an auxiliary disability
benefit, the spouse can earn a right to the QPSA or QJSA
by being married for 1 year prior to the annuity start date.
Is this correct?

I do not believe the "pure subsidy" disability benefit is subject to the spousal consent since it has no impact on the spouses benefit. The biggest problem we see is that the Plan Administrator sometimes forgets to get the disabled participant's "retirement" election at the time the benefit switches from a disabilty benefit to a retirement benefit.