It'll be possible for a couple if weeks so get some pics took quick lol , the Oscar will eat everthing or choke to death trying either that ir you'll have one pack of meeeeen goldfish on your hands lol
Oh the gold fish temperature situation. They get treated like **** so often that I think they'd be ok with a 75° tank (not a "goldfish" bowl) with an owner that actually changes the water...
Before I knew about goldfish liking cooler temps I had a tank with two 8"-10" oscars. And three 3-4" goldfish. They got along just fine. Goldie's ended up huge. It's almost always situational. Now if you want to take your time/chances experimenting...that's up to you