First, that hardened buckskin is not buckskin but synthetic and was also under a program for replacement. It must be replaced if touch is to be improved. Replace catcher covering too. Protocol is to remove the damper levers and flip hammers forward for replacement of butt buckskin.
The most common problem with poor jack reset is insufficient lost motion, so gently pull back on the hammer rest rail to be sure all hammers follow slightly. Shim rail w key bushing material if needed. Every new vertical had this problem in the 1980s.
Baldwin vertical piano actions are capable of developing action center sluggishness and a mild case might show first with the use of the sustain pedal. Here it's helpful to release the soft pedal (hammer rest rail) quickly and note any slow returning hammers. But whip flanges are less easy to test. Suspect them too if reset is slow with the sustain pedal use.
Balance rail key bushings usually give problems first with keys which have more side angle, as the bushings wear faster and will hang up on return. Replacement is required. Also, In wet climes or with an un-used piano, suspect tight front or balance key bushings.
Also, back leading was ignored by Baldwin and improves performance dramatically, use a touch weight protocol to locate lead.
Bill Shull