Seems to me, the bugs are at the IRS level itself. I do not see where in Schedule 1 it refers to entry from Form 8960 (I see that in Schedule 2).
Also, the rejection says that the threshold for entry should be 125000, but TT automatically calculates it to be 250000 for 'married filing jointly' filers and does not allow the user to change it manually. This could be fixed on the TT side, but not sure if IRS would still take it
