I was able to finally find a solution that doesn't involve reinstalling. Go to Steam Settings > Downloads > Clear Download Cache. This causes you to have to restart Steam. Steam didn't restart for me, so I restarted my computer. Steam started up and I was able to rejoin the match.
An explanation of a recent day:
1. Enter queue.
2. Open hero selection and click "Test Hero" as soon as queue pops.
3. Instead of joining the game, I went into hero sandbox.
4. While in hero sandbox, attempting to leave the sandbox produces a "you will abandon this match" message.
5. I killed...
Match ID: 33743074. Around 11:05 when Vindicta uses flight, you can see that she teleports to the tower. The ascending part on flight seems to be affected by the tower in middle. During the ascend, she seemingly gets clipped. This reddit thread with Lash ult also seems to have a similar issue.
It seems Sinclair will maintain the direction caused from loss of control after teleporting. The problem I had was that I had the assistant on top of a tower, I got hooked by Bebop, then uppercutted. I teleported back mid-uppercut and the movement from the uppercut kept going after the teleport...