No, they are specifically *not* both right.
General Relativity was wrong when it had the Cosmological Constant (i.e. a static, non-expanding universe), and it is wrong today without it. It still fails to predict orbital positions, for instance, and it is soundly refuted by the energy and Gravity realities of Quantum Mechanics.
Quantum Mechanics may or may not be incomplete, but at least it doesn't have General Relativity's glaring flaws.