I'm happy to report that Benny seems to be back on track in terms of sleeping. He still cries (for about two minutes, rather than two hours) when we put him to bed, but he's falling asleep faster and sleeping more soundly.
It turns out that he's had a sinus infection for awhile. I finally took him to the doctor for his cough last week. The cough has been lingering (getting better, getting worse) for about six weeks. It's really no wonder he hasn't been sleeping well. He was probably uncomfortable. So, he's on antibiotics for the next few days. And how he LOVES his medicine.
Although I hate to hear Benny "cry it out," I'm ultimately glad that we didn't start any new routines at bedtime. He can still entertain himself in his crib and put himself to sleep. Those are some important skills for an almost-two-year-old bear!