It sure feels like it, but for the reasoning above. 1-2 players do make it to WTF semi's every time one player goes 3-0 and the rest 1-2.
In any event Thiem and Goffin have trained together and even did so at this event despite being in the same group
So Goffin has all the reasons in the world to withdraw from this match:
1. Plenty of court time with the Nadal match
2. Anchoring Belgium in Davis Cup final that starts in 7 days where the entire French team will be trying to take Goffin down including Pouille against whom Goffin is 0-3

3. With Goffin's taped knee hampering him at the end of the Nadal match, the 2nd RR thrashing either indicates Dimitrov is in the form of his life or Goffin's knee was worsened by this first match. Simply being tired after the Nadal match is another possibility, but with a full day off this should not have been an issue.
4. Goffin well knows that the die is cast; his SF opponent will be Federer who absolutely thrashed him recently in Basel. The toughest opponent imaginable awaits Goffin as a reward for winning on Friday.
5. Goffin has already secured 200 ranking points at this event. He's in little danger of losing top 8 seeding at Auz and has almost no chance to make top 4.
6. The kicker is Thiem is a friend of sorts.
Goffin withdrawing puts Thiem in the semifinal match with Federer.
Why would Goffin not withdraw if it puts his friend Thiem into the semifinals given all of the above? Perhaps he intends to show for the match and play for a set and then withdraw giving way for Thiem. The tournament could be pressuring him to play, but it just makes little sense with Federer looming and a withdraw later just screws up the tournament completely with Querrey as an alternate not an option under the rules.
Looks like some serious ******** the most likely outcome.