I'd say otherwise, reason why they were able to add few more romance dialogues was because they got actor available because of Heart of Stone development. I don't see how adding romance dialogues convinced them to hire Vesemir actor again and add few more lines with him as well.
The comments on Geralt's mark appeared (in the base game) at the same time as the romance "tweaks", and they are short and not very well acted and recorded, so they do look to me like something that was quickly tacked on, rather than planned from the beginning. The Vesemir lines are not in the files of the main game, but it is possible that they were already recorded before its release. It also depends on which of the actors voiced other character(s) in Hearts of Stone. I recall someone mentioning an interview with Geralt's voice actor where he said work on the expansions already began during the development of TW3.