Well, that bites!
Not sure what tailgate lock you bought, but if it was the Pop and Lock I recommend buying the warranty. My first one broke (the tab on handle that actuates the opening mechanism) and now my 2nd one won’t lock (bought Amazon warranty, haven’t figured out how to get replacement). Neither lasted a full year.
If you found another option, please post it.
Note I do have foam around the tailgate for dust mitigation, so it is somewhat tighter than normal, though the factory handle had no issues.
I strongly recommend putting in a gate latch on your tailgate and not just relying on the lockable latch. Especially if you’re going to be parked in the PDX area. My 2 cents.
You’re 2 cents make a lot of sense and I’ll work up an idea on a way to lock things up and not relying on what I have now. I live in Santa Cruz which has an equal amount of riff raff night crawlers.