Hmm, it's hard to say because some torrents only have 1 or 2 trackers and others have a bunch. When there are several trackers it is also usual that some of them fail for various reasons, e.g. overloaded or offline etc. If the torrent/magnet you used only had two trackers in it, then it is working and just one of the trackers failed to report back in time so timed-out/failed.
If you wanna trouble-shoot it further to make sure, then you can try again with logging enabled and paste the log here or to me in PM if you prefer, so I can see if it connects to both trackers at a time(and one fails) or just one, and then moves over to the next only if that fails. The log will be on the desktop afterwards and named deluge.log.
Press win+R and copy/paste the following followed by return:
"%ProgramFiles%\Deluge\deluge-debug.exe" -L error -l "%UserProfile%\Desktop\deluge.log"
In this specific incidence though, if it's correct that the torrent only has 2 trackers, then the announce_to_all_trackers option doesn't change anything really, since of the two trackers only one works/replies, unless it was just overworked previously.