Hi Priya,
I personally know how frustrating it could be.
Hey, first of all let me make it clear that I am here..not to provide any solution to the problem...but, just to share my experience similar to your's...just to say that you are not alone

I used to make pretty decent dosas for years without any problem.But I I was bitten by the improvisation bug when I saw a recipe for
restaurant style crispy paper thin dosa on the net...

Apart from the regular rice and dal I have added poha,generous amount of methi seeds,sugar and cooking soda as per the recipe.
The resultant batter didn't get the pinkish blush as yours....

,but smelt as offensive

.
Apart from the normal dosas,I tried utappams with liberal additions of vegetables...and paniyarams....because just like you I didn't have the heart to throw the batter drown the drain.....but all efforts gone in vain and realisation dawned on me.

It's better to discard the batter than not only wasting additional oil and vegetables but most importantly time and energy on it.
And now I am back to my tried and trusted recipe even though it doesn't promise any
awesome results ...at least I am sure that it wont' be
awful either.....lesson learnt...