Dogs are typically much harder to socialize as they age. They become rigid in their routines and less open to new experiences, so it takes much more time to try address their fear and anxiety.
The most important thing you can do is separate the two via a physical boundary that still allows them to view each other (e.g., crating them next to each other). This will allow them to get used to the others presence. As the yorkie starts to settle down, you can start to introduce limited physical contact / play time.
During these play times, you will need to monitor them carefully to ensure you can read the body language. The puppy is curious and playful by nature, but will nip and try to rough house with the yorkie - which the yorkie is not understanding. Growling, showing teeth, or even licking lips and yawning can be signs of aggression or anxiety. When this happens, you go back to non-physical interactions to let them settle down.
Another trick is to use a muzzle. Obviously, this prevents the danger of biting or attacking, but it can also make both dogs calmer and more receptive to having a positive experience.
All hope is not yet lost, but there is much more involved in socializing an older dog compared to socializing a puppy.
