Exactly, the autofill results use the Google database entries. Selecting an autofill result will route you to the Google pin location, unless there is an exact waze match in which case you will be routed to the waze stop point. If you complete the search or ask for more options you are given a set of best matches from both waze and Google, but with the waze results favored. In this case, it seems that the match is not good enough to have the autofill result route to the waze pin. But it is good enough that the Google result does show on the waze tab in the app.
Some other examples with slightly different results. Take 2172 Mulberry Hill Rd, Annapolis, Maryland. This address is in both the Google database and the waze database. The waze stop point is at the end of the driveway that is far from the closest point on the road to the house, where the Google pin is. As there is a perfect match here, selecting either the autofill result or the search result on the waze tab will route me to the waze stop point at the end of the driveway. (If I switch the search result to the Google tab and select that entry, I am routed to the closest point on the road to the house.)
Another example is 355 Montecristo Ct. Here waze is using the CDP so its "355 Montecristo Ct, Odenton, MD," while Google is using the mailing ZIP so its "355 Montecristo Court, Severn, MD" The autofill result is the Google result "355 Montecristo Ct, Severn, MD United States" routing to it shows the destination flag at the Google pin location. If you complete the search you get both "355 Montecristo Court, Severn, MD" and "355 Montecristo Ct, Odenton, MD" as results. As the city names are different, waze doesn't know they are the same place. If you choose the "Severn" entry you get the destination flag at the Google pin. If you choose the "Odenton" entry you get the destination flag at the waze stop point on the road.