You need four ghast tears and eyes of ender. IMO the former is arguably the harder of the two to acquire, simply due to how rare ghasts seem to be. I don't know how hard those things are to acquire in the Valour nether, but given how quickly players find nether fortresses in Supply I wouldn't expect it to be that hard. The respawned dragon just isn't worth very much in terms of XP.
This is what I've been doing on supply, this week: Collecting hardened clay. While it is true that gold deposits exist up to the top of the stone layers, in these biomes, in supply world, there are very few visible. Inside of abandoned mineshafts is the best area to mine gold.
You have done as well as you could. That is all there is to being great. GG.
Just a little tip for supercaving. If you find yourself in big trouble with a lot of close ranged hostile mobs (spiders and zombies) and you have a shield, Look for a creeper and start running around in a circle around the mobs. They'll get all bunched up in a group then lead a creeper over. Use your shield and let the creeper explode.. Then ITS RAINING MOBS HALLELUJAH
I usually carry torches in my left hand when super caving, so I never use a shield. I tried it for the first time last night and it worked wonders. Now I have less to fear from creepers (which I hate.)
Torches in shield hand with sword in normal hand, running round like a headless chicken this is fast enough to light the place up fully without being hurt. Then use a shield and sword to lure all mobs into one area (mainly a pit which I placed a ladder) then I lure in the creepers and wait then BOOM, mobs dead and cave lit up