Apple ID: 'Migrate Purchases' option missing

Issues Migrating Purchases and Subscriptions from One Account to Another

Years ago I ended up with two Apple accounts, one for subscriptions, music, and purchases (apps) and the other as my iCloud account (iCloud drive, mail, etc.). I spoke with Apple the other day to ask if there was any hope in getting to one account, and they said I could use a built in migration tool to move the former (purchases) to the latter (iCloud). I was really excited... Except it doesn't work. They sent me here:

Migrate purchases from one Apple Account to another Apple Account - Apple Support

I got through the pre-requisites, making sure there's no family sharing, etc. Then at step four it breaks down: "Scroll down, then tap Migrate Purchases." There's no "Migrate Purchases" choice on my iPad or iPhone. It just doesn't exist. I've gone through the pre-requisites again and again, checked two-factor authentication... Nothing seems to add that choice.

I was wondering if anyone else had been here and, if so, had figured out a way forward. I'll get back online next weekend with Apple but, in the meantime, I've found the community suggestions to be more helpful in the past so thought I'd toss this out there. Thanks!