Tara ji is apparently worried that SPS will get killed by his aunt if the truth is out to everyone.
There's a reasonably easy way out 
Only tell SPS (and no one else) that Dhruv is her husband and D is Shaurya's father.
Tell SPS that Dhruv and she have a method to go so far away that nobody will find them. If SPS presses, just give a kasam.
Ask Dhruv to wait near Navrangvan for a day or so
Take Shaurya separately there.
All three disappear; nobody puts the blame on SPS; everyone happy.
Ofc the serial won't last
, and it'll be a tad difficult to explain things to Shaurya in the 21st, but the latter part can be managed.