Yesterday, I figure out a much simpler way.
For anyone eventually interested, Text+ does all the dolly-in messy job above. Check the Z Center adjustment in Layout tab. Objectively, that's it.
----------------PS for newbies like me----------------
Unless you want to use the Spline space to ease in/out the animations, you don't have to be on Fusion tab, but if you do so, on the Edit page, right-click the clip and set it up as a new Fusion clip.
If you prefer to build it on the Edit page, (a) position the bg video on secondary track, (b) on it's composite mode, choose Multiply and (c) for now, disable it. Right below, (d) insert the Text+ initially* with the same duration as video above. For a full transparency (e) the font color must be white; if you choose light yellow or green, you will see the bg video, but as if the title has wear color glasses. Also, the darker the font color, the less bg you see and the same applies to the background, which is why it's black. Finally, (f) to get the solid red color solid at the beginning of the animation, turn the bg video 0% opaque and animate to increase opacity to 100% the same duration as the font turns red to white.
Anything else you want to modify on the title animation from here is up to you.
* If you want to include more titles after this on the same video above, first, finish this one. Then, trim the video with blade and return the composite mode to normal. From this point on, you can put it on track 1 and another title on track 2, as well as continue adding titles and swapping title and video position if needed. If you want to include titles before this dolly-in title, I'd mark the start point for this title and separate 1s before it on timeline before make it.