Judging from this tweet it looks like we will be able to get those skins
Play alongside us. Play against us. Just jump online and get into an Evolve match between 9:00 PM PT on Thursday, March 5th and 9:00 PM PT on Sunday, March 8th and metallic glory is yours. (These skins will be delivered to players sometime after the weekend ends, but before Saturday, March 14th.)
And now there’s a proper topic for it
Edit 2: Quotes from Macman clarifying the situation
We want to give back to you. We also want to show our appreciation for your immense support over the last month, for believing in Evolve – and in us – from the very beginning. So, this weekend only, play a few rounds of Evolve and we will reward you with the coveted TRS Gold Skins for Goliath, Kraken and Wraith – free.