give it some time. still three weeks out before booster boxes end. it does suck that there are still people that continue to benefit from the cash exploit from almost a year ago now vulturing and jackyl gathering plucking the cosmic chroma and the smoke chroma from the time capsule etc etc.
I opened 3 boosters and on the 3rd 1 i got a cosmic chroma and i sold it for $999,999,999 ,it was gone in about 2 secs
I did sell stuff on trade channel before. Also the trade window has an option to put up the item and not confirming the trade until you see the other party's goods/money. If you confirm before you trade, then that's all on you, not the player you traded with.