H'mmm. The medical summary at the bottom of the original posting begins

       To date, the pathogenesis of systemic lupus erythematosus (SLE)
       remains unclear. By critically analyzing clinical facts and
       laboratory data, a hypothesis is proposed: drug-induced lupus
       erythematosus (DILE) is linked to a deficiency in Coenzyme A
       (CoA) that is secondary to a deficiency in pantothenic acid.

and continues

       This hypothesis is used to explain the high incidence of SLE in
       females, the role of sex hormones in this disease and the
       mechanism underlying a flare. ... The protean clinical
       presentation of SLE is attributed to co-existing deficiencies of
       dietary factors in addition to pantothenic acid. ... Treatment
       is replacement therapy with doses of pantothenic acid that is
       hundreds of times higher than that of the Dietary Reference
       Intake (DRI) and other vitamins. Using this method, 12 SLE
       females were studied with promising results.

This I interpret as saying that the "pantothenic deficiency hypothesis"
arose from studies of Drug-Induced Lupus and has been directly applied
to Systemic lupus. That's fair, as a hypothesis is a possible
explanation of a set of observations capable of being tested.

Your kingsoopers link says:

       Systemic lupus erythematosus (SLE) is an autoimmune illness that
       causes a characteristic rash accompanied by inflammation of
       connective tissue, particularly joints, throughout the body. In
       autoimmune diseases, the immune system attacks the body instead
       of protecting it. Kidney, lung, and vascular damage are
       potential problems resulting from SLE.

...

       Discoid lupus erythematosus (DLE) is a milder form of lupus that
       affects the skin. Like SLE, it's not known what causes DLE,
       though sun exposure may trigger the first outbreak. DLE is most
       common among women in their thirties.

Then a table gives a 1-star rating to the supplements Pantothenic acid &
Vitamin E and the herb Astragalus; defined below the box as "An herb is
primarily supported by traditional use, or the herb or supplement has
little scientific support and/or minimal health benefit."

Lower down it says:

       Preliminary research suggests that pantothenic acid, when taken
       together with vitamin E, may help those with DLE. In one trial,
       taking 10 to 15 grams of pantothenic acid per day with 1,500 to
       3,000 IU of vitamin E per day for as long as 19 months, helped
       67 people with DLE. Pantothenic acid by itself for shorter
       periods of time in lower amounts has been reported to fail. The
       amounts of pantothenic acid and vitamin E used in the first
       trial are very high and should not be taken without the
       supervision of a physician.

and

       One Chinese preliminary trial also found that astragalus could
       decrease overactive immune function in people with systemic
       lupus erythematosus. However, much more research is needed to
       know whether astragalus is safe in lupus or any other autoimmune
       disease.

I would interpret this as meaning that Pantothenic acid with Vitamin E,
and the herb Astragalus, are maybe worth a carefully controlled medical
trial in both discoid and systemic lupus. Or putting it differently,
watch this space but don't try it at home.