What guidance has the Army put out regarding soldiers who are unable to do one of the mandatory events on the ACFT?

If your permanent profile prohibits the SDC, then the SDC you will not do. If your permanent profile does NOT prohibit the SDC, then you need to talk with your PCP to get your profile updated.

The bare minimum for those on permanent profile is you have to be able to pass an aerobic event. This is from the official ACFT page as well:

"All permanent profiles must be updated by the Soldier’s medical provider to reflect the ACFT events permitted or prohibited. Soldiers must test on all events within the limits of their permanent profile. The minimum number of events a Soldier must take is one aerobic event (run, stationary bike, swim, row, or walk)."

Let's walk that back.
What guidance have you seen that there ARE any mandatory events? I mean AR's, FM's, MILPERS, ALARACTS, OPRDS etc...
Not one of the thousands of news stories on the subject.

The latest guidance on the Army.mil ACFT site is only that you will do the ACFT IAW your profile, and at least one aerobic event must be done. None of the events are mandatory. You just need at least one aerobic event, just like with the APFT.

That's it.