Most recent update: Spoke to four more people at EA so far today on two separate calls.
On the first call, I ultimately got someone on the tech team who seemed to at least understand the solution and was just waiting on a consultant to confirm he could put the NPC version of SSB into my game (so I could tap him and trigger the questline). He mentioned that he had done this once before, but it had been awhile, so he was trying to remember the process and wanted a consultant's help. Unfortunately the call dropped (on my end) and he tried to call back but went straight to voicemail (awful timing for bad cell service).
Of course, when you call back, you're not guaranteed the same rep (in reality, I'm sure there's almost zero chance of it). So the second call went to two different reps who then apparently spoke to a consultant who had no idea how to fix the problem. This meant they tried to read to me from the same standard script (SSB randomly spawns, tap him once, then three times, then five, he's often reported as stuck but he's not really, etc.). Basically, no one on this call knew how to implement the fix mentioned above.
I'll try again a little later today and report back.