The possibility of two sticks from different packages working together is increased the greater number of things that are matched. Using same brand and even same model is **no guarantee** as vendors off switch memory suppliers. Corsair Vengeance pro / Dominator is a good example as they switched module providers midstream and timings changed from 10-12-12-28 to 10-12-12-31.
So try and
Match Speed
Match Timings
Match Vendor
Match Module Supplier
Match Voltage
The more of those you can accomplish, the better chance you have. Still, no guarantees if they didn't come in the same package