Hi. Since latest patch (as far as my memory can tell) the HRE Emergency Repair (ER) action does not work for the Regnitz Cathedral. It will show the Requirment: In influence regardless of the Cathedral being in influence.
Please also note the tooltip indicates a 3 second production time which is unusual.
This should be easily replicable as I’ve seen this in many subsequent games. It seems the bug does not apply for the original TC, II landmark (Chapel) and IV landmark (Swabia). It seems this bugged mechanism also applies to the IV landmark Elzbach Palace.