He never liked the idea that she was looking into this, he has made that clear from the beginning…
What that portends, going forward, is continued friction on the question of his real identity.
The story we’ve told this year, of Liz’s quest to find out Raymond Reddington’s identity — and the answer that Dom gave her in Episode 19 — is one that brings Liz even closer to Raymond Reddington, not farther apart from him.