First scroll to the approximate time, then use a pinch-out (two fingers spreading apart) gesture on the timeline to zoom in. This gives you finer control over the time.
That said, here’s an existing Wishlist topic where you can vote for direct time entry for playback:
In the future PLEASE SEARCH the Wishlist and Roadmap categories before submitting a new Wishlist topic. Use these links to search each category:
Search Wishlist (enter your search word/s after Wishlist in the search box)
Search Roadmap (enter your search word/s after Roadmap in the search box)
You can now hop on over to the merged topic and VOTE for it. For your vote to count, you must click the VOTE button at the top of the page.