Carbon and PDC are owned by the same company. Carbon is the flag ship skin for Merge it's probably the safest place to deposit. It's not really Merge that is losing the money, the companies operating some of the skins are losing money because they can't get new players in and deposits flowing. The risk is that a skin you choose will close down, but typically they will allow funds to be transfered to another skin in the way FeltStars allowed.