If you are using voiced speech or have set an invisible font, SpeechBubble calls Character.Say() internally to handle the speech animation and timing of the display. As I recall, you set an invisible font earlier to workaround a cutscene bug. So Game.IgnoreUserInputAfterTextTimeoutMs should work without any changes to the module code.
Edit: However, this setting doesn't actually do what you're interested in: it only ignores input after the last line timed out, not if you dismissed it. If you hold down a button, AGS will still speed through the dialog at high speed.
This behavior is by design, but I have also had the impression that the speed has increased lately (or maybe I'm just getting old...). It would be good to be able to control how fast it happens (I would guess it's at the key-repeat speed for holding down a keyboard key, but does that also apply to mouse-button presses?), and also ensure that a slightly longer click/button press doesn't accidentally skip two lines.
I've also split this continuing discussion into its own thread since the "(SOLVED)" part of the title kept annoying me. Arguably it should be merged with the module thread, though.