Since you said in T-SQL I won't bother trying a PoSH solution. The way I'd typically do something like that is to use a linked server from DEV to Prod (or vice-versa), dump the results of the 2 procs into temp tables, and do an EXCEPT. Something like this:

INSERT INTO #prod

EXEC linkedservername.databasename.schemaname.procname;

INSERT INTO #dev

EXEC schemaname.procname;

/* this returns all the rows in prod not in dev

SELECT *

FROM #prod

EXCEPT

SELECT *

FROM #dev AS d;

You could also reverse the order of the queries in the EXCEPT to find out if there are rows in Dev not in Prod.