If your coworker’s TPU print “delaminated” easily, either by pulling apart at the layer lines or via the individual print lines tearing within a layer, he was either printing it too cold or too fast, or both. Which is a common mistake. People see the print temperatures listed on the side of the spool that are similar to PLA and assume it can just be printed like PLA. This is not the case if you want acceptable results.

You have to print TPU slowly, and if you want the strongest possible part and don’t have any tricky overhangs to deal with, you also want to print it towards the upper end of its temperature range. People will be tempted to lower the temperature as far as possible before the stuff just flat out stops coming out of the nozzle in a vain attempt to combat stringing, but this is a fool’s errand. You can never get TPU to stop stringing, so don’t even bother to try. Just clean up your finished part with a lighter after it’s done.

TPU is one of the very few materials – arguably the only such material – capable of being printed by a consumer level printer that, when printed correctly, is functionally isotropic. That is, its strength and properties are the same in all directions. Both along and against the layer lines. TPU that’s been printed right sticks to itself extremely well.

You have already correctly guessed that this property makes removing supports from it kind of tricky. I’ve never been able to achieve supports with TPU that can cleanly tear off like with PLA and other more rigid materials. You’re going to have to resign yourself to cutting or shaving them off, at least in some capacity. For the ones inside your shoe, this may present some difficulty.

The others are correct about drying the filament, also. Get a filament dryer that can feed directly into your printer. Even a dinky one will do; you don’t need high or precise temperatures for TPU drying. I have the $30 OG Sunlu one and it works fine for me.