Are you serious? I got the impression the loan was for an initial month with a view to extending it, so why would anything have changed? We won't get to see much of him in that month, so the loan might as well be extended for another month anyway, as I'd expect Everton are paying most of his wages.
If he's a player we tried to get in the summer and then went after again in the autumn, why on earth would we bin him off after 20 minutes?
The guy's on the fringes of a good Premier League squad, has recent L2 experience (and as a 19 year old captain) and international experience - all of that puts him ahead of Wildig in my book. Don't get me wrong, I'll be happy to see Wildig do well and stay on but I'll be astonished and disappointed if we give up on Wallace now. I don't think we will.
I don't think Everton would want him back on the strength of one good L2 performance. I think he might be here for the season.