I have seen Prashad quite often, hardly missed India/PAK games that time. I don't think it's fair to judge him along with Thakur. It's not just "some" success - guy was quite good for at least 5-6 years, but he was a seem bowler - needed to pitch it up and most of the Indian games played on roads in 90s, he went for plenty. But, he had 7 5fors & a 10for In Test.
In between, Prashad has a great SAF tour in 1996-7, a good English tour in 1996, he took like 6/6 with 2nd ball in that famous Chennai Test (bowled really well in that series), bowled well in 1999 NZ tour. His biggest problem was, during his time IND played too many games with SRL, either at home or in SRL - both on roads, and that time for 4-5 years, SRL truly was the best team in world for such wickets; they man handled him like a torture.
It's not fair to put Prashad down for this Thakur guy.