I think I see the problem. Two words: mink oil. That stuff should never be used on modern boots. That’s because the leather tanning process is different from olden days, when mink oil helped soften brutally hard leather. Now, with chromium tanning, boot leather comes pretty soft and stays that way with reasonable care. Mink oil simply turns it to mush. Plus, boots today have quite a bit of glue in them, as the midsole typically is cemented to both the sole and the upper. Oil can work its way into the glued joint and make the boot “delaminate,” a fancy word for “fall apart.” It sounds as if your shoes are in some fashion delaminating.
I could be wrong. Boots are like any other human-made productonce in a while you get a bad pair. And maybe you hadn’t even applied any mink oil before. You can try sending them back to Asolo with a note, and see what happens. (Mailing address in the U.S. is: Asolo North America, 190 Hanover Street, Lebanon, NH 03766.) Attach a label that directs the boot to “Warranty Repair.” Who knows, maybe they’ll just send you a new pair.
But, in the future, steer clear of the oil. Use a silicon- or wax-based leather treatment or waterproofer. Your boots will last much, much longer.