This also happened last weekend and again just now. In the 1st room the 1st switch is not showing. I tried multiple times even wait for 5 minutes.
If you read the text, Riddler says to get to the point. You need to walk on the arrow on the ground in front of the garage door.
I know where the switch pops at. It has not been showing the last few times I went to the spot. I nevere payed attention to that but got it to pop anyways. If I play dc this week I'll try your tip.