Looking for some advice for how to handle my latest frustration with TK as an E+ member...

I've been seeking a one-way flight from JNB-IST-ORD for myself and my partner which had upgrade space. I wanted to use my E+ voucher(s) and my partner would use my miles. After much searching on ExpertFlyer, I finally found options that had at least 4J seats showing on both legs -- although no J availability for combined trip. I was happy to book this and use 2 vouchers for me + miles for each leg for my partner.

Booked flights on TK.com. Immediately was shown options to upgrade with miles for both of us on both legs. Great! Called TK call center and they also confirmed availability. Agent proceeded and upgraded me first with my vouchers. All good! Then they say there is now no upgrade availability on the JNB-IST route (despite before there being the offer for both of us).

She then offered just to upgrade the IST-ORD route for my partner, which I accepted; however, she could never get the miles payment to process. Told me to try again in an hour. Now when I log in to the online booking, it's not showing any upgrade availability.

I'm in J for both legs, and my partner is stuck in Economy despite it originally showing enough upgrades for both of us.

Any suggestions for how I could fix this? Don't want to sleep on the couch for the next year