[I am not an expert]
I think the answer is No (unless you want to write some very detailed code).
Freezing is done on a per-layer basis, so either all the embeddings are trainable or all of them are not.
I’m not sure it would even make sense to try to write code to alter only your new embeddings.  The whole Bert only works in context.
Are you sure you have enough data to train Bert to make useful embeddings of your new names?