>The only markets where you can short bitcoin are sketchy overseas exchanges
probably because no reputable country's SEC equivalent would let that happen
>low volumes
bitfinex is one of the largest exchanges by volume
>a history of problems both depositing and withdrawing money.
if this is happening, it's not happening with any of the major exchanges that support margin trading. any time depositing/withdraw issues appear on an exchange, prices quickly deviate from the rest of the market as the supply of fiat/crypto diminishes.
You can short Bitcoin on the Chicago Mercantile Exchange:
No serious investor is going to be putting money in bitfinex or whatever to short bitcoin.