Boiling lentils in chicken stock?
Yes, they will take up some of the flavor of the stock.  However:

1) the flavor will be subtle and hard to detect, especially if you are spicing the dal heavily (as you usually do with Indian food)

2) it's not that authentic, since Indian food is often vegetarian.

Personally, I'd freeze the chicken stock and use it for something else.  Or make Turkish lentil soup, which does call for a stock base.