yes, you are right.
we too, have in table SAPSID a column with TAPMLBnn entries,
but in our R3TOOLS implementation, these values in that column are not used by any pgm.
so the R3TOOLS library is different in several customer installations.
but, by the way, you could avoid changing the mentioned steps and entries
by renaming the name of the TAPMLBnn (not rename the resourceName) to the value you have had before.
=> wrkcfgsts *dev tapmlb*
=> option 2 = vryoff
=> option 8 => wrkdevd tapmlb*
=> option 7 = rename
=> vryon again
=> INZBRM *DEVICE
..... and that's it.
HTH
Christoph