If your build doesn't include mystic expansion, compress cooldown or duration extender and you try to quickbuy the tier 3 upgrades with your minion you won't get the popup to pick which ability to imbue and will get the minion stuck at the shop.
I think the main issue is that when you right click either tier 3 items it also queues the tier 1/2 item to purchase first which it shouldn't be doing since the tier 3 isn't an imbue item, and if you remove the tier 1/2 item from the quickbuy queue and leave the tier 3 it buys it just fine.
Also for some reason when you quickbuy transcendent cooldown it gives you the popup.
Tested in sandbox with this build setup

I think the main issue is that when you right click either tier 3 items it also queues the tier 1/2 item to purchase first which it shouldn't be doing since the tier 3 isn't an imbue item, and if you remove the tier 1/2 item from the quickbuy queue and leave the tier 3 it buys it just fine.
Also for some reason when you quickbuy transcendent cooldown it gives you the popup.
Tested in sandbox with this build setup

