It is looking very likely because on Monday December 2, 2019, the British Board of Film Classification published information about the first trailer, including confirming the title of Ghostbusters: Afterlife and it will have a runtime of 2 minutes and 28 seconds.
Given premieres for Star Wars Episode IX and Jumanji: The Next Level should be starting this week and next in addition to trailers for 007 and Black Widow just came out, it looks very likely the trailer for Afterlife will come out late this week or sometime next week.
Sometimes when the updates across Fandom go into effect at the various wikis, there's a glitch for a day or two. This glitch of images not showing up in articles when they are really there is a common one. It should be back to normal.
I don't think they can avoid using Slimer at this point.
Very exciting announcement and fun teaser of things to come.