Are these two getting ready to spawn?

Hello, I got four larger discus about 18 days ago. They are now in a quarantine tank and they all have been doing great so far. But yesterday night I noticed weird behavior in the tank. The two red turquoise were behind the piece of driftwood and displaying what I think is pairing/spawning behavior. They were chasing the two turquoise away every time they tried to get close to them. I also noticed what I think was a breeding tube on one of them. They were spookier than normal and were not happy with me near the tank. So I setup a time lapse camera and got this clip. I don't have a lot of experience with discus but the behavior was similar to what you see with angels when they are getting ready to spawn. Would love to hear some comments and/or suggestions. Thanks in advance.

https://youtu.be/IP1t6p9lsI4

I don't see any loving behavior. To me they act like 2 males. Why are they in QT?

I have two that have showing signs for 3 weeks. Pecking, shaking, with nothing yet. Surprise is sometimes the best discovery least when you are expecting it to happen.