ShortingNobody shorts this kind of stock. Its illiquid and from my perch I could drive it up or down 20% in 60 seconds.
There is also a cost to borrow a stock if you want to short...
In all likelihood what you are seeing on the OTC is scalpers who buy in canada for instance and simultaneously sell for a penny more on the OTC - arbitrage. This occurs with most stock that trade on both markets. When markets close their positions get netted out.