It seems like tokpie.com is legit one and another domain that used ,io can be considered as a scam. If you are feeling doubt about that and you can ask tokpie admin directly on the telegram group.
As far as i know, tokpie admin is also active on there too.
So, I searched around, and I found that on CMC and on their bitcointalk thread, they refer to tokpie.IO
https://coinmarketcap.com/exchanges/tokpie/
https://bitcointalksearch.org/topic/tokpie-makes-your-dream-real-bounty-stakes-trading-5050817
But also, on the same bitcointalk thread above, you find tokpie.com
So, I guess it's both IO and COM domains