I have a hard time seeing the point of wealthfront given their extra fees when there are plenty of low fee, easy, and good investment options like VTSAX. The only semi compelling thing they offer IMO is the automated tax loss harvesting, but while that is helpful it's worth less in a low bracket, which you probably are as I think I remember you're a teacher. Also manual tax loss harvesting isn't that hard.
It sounds like the $299 is probably an already harvested loss. If you have any realized gains (sell a stock that has gone up in value, or a fund that distributes gains) the losses will offset that. What you need to find out is what your basis is in the wealthfront investments. If they've had gains since they were purchased you'll owe taxes on those. It sounds like any gains will be short term, so you'll pay taxes at your current marginal state and federal rate. Assuming the $299 in losses are also short term, those will offset any gains. Whatever gains you have, if any, probably aren't that much so I'd probably sell what you have with wealthfront and move it to Vanguard. You might also be able to move the investments "in kind" (without selling) to vanguard, but you'll want to check what kinds of fees there might be to sell at vanguard depending on what the investments are.