Plaudit and pundit are actually from entirely different
parts of the globe.
Pundit:
[a. HindW pa:,it:—Skr. pa:,ita learned, skilled; as n., a learned man. So Pg. pandito, põdito (16–17th c.), F. pandit, formerly pandite, -decte.]
a. A learned Hindu; one versed in Sanskrit and in the philosophy, religion, and jurisprudence of India.
The Pundit of the Supreme Court (in India) was a Hindu Law-Officer, whose duty it was to advise the English Judges when needful on questions of Hindu Law. The office became extinct on the constitution of the ‘High Court’ in 1862.

wwh's explanation of the origin of plaudit is correct.