In this case, I might consider progressively abbreviating the values to avoid unnecessarily overflowing to another key. You’ve already started by omitting the proper but inessential periods in postnominals like C.N.P. In desperation, I might then omit the commas, the generational suffixes, the middle initials, and eventually the given names. Or I might assume that the practitioners are listed in seniority order and list only as many as I can fit, relegating the rest to a :1 or a note=*. You won’t be able to search for every doctor by their fully qualified name, but there’s only so much we can do.