Best method to add a tee to AC drain line

I want to add a tee coupling to my existing AC drain line to accommodate the drainage of newly added dehumidifier condensation water. I did some research myself and debating between using a saddle tee or a regular tee with a telescope coupling. I lean towards the telescope coupling because it offers a cleaner installation, eliminating the need for drilling and potential debris left inside the PVC pipe. However, I'm concerned whether the telescope coupling might alter the natural downhill tilt of the drain pipe, potentially causing water trapping issues.

What is the best way to accomplish my goal?

Edit: my furnace features two 3/4" drain lines: a primary line, complete with a clean-out, and a secondary line. I am thinking about connect my dehumidifier's drain line to the secondary line. The dehumidifier's drain line is from a 3/8-inch vinyl tubing from a condensation pump.