Fantastic job on the Mav and video editing! I nearly spit up my coffee multiple times throughout this masterpiece. Prayers and best wishes to your Sis. 👍
You just have to work it in with your hands and pull the velcro straps up tight to keep it taught. The velcro straps at the top and bottom get attached to the back of the seat, they do not strap downward. I hope I'm not misunderstanding you.
You could try these and the connectors appear much more robust...
https://www.uprproducts.com/upr-plug-n-play-pcv-snap-fitting-45-angle-for-oil-catch-can-3-8-1-2-5-8/
You will need to insert your hand where I marked below and then it will be up and slightly to your left.
You will feel the rigid hose and will need to press the clip as you pull it off of each elbow. BE CAREFUL because the clips break easy. If you break the clip, you will have to get a...
Stellar work! Now you just have to replace the chrome emblems with a custom painted HPR/Black theme and black out the front grill bar and it would be complete. (y)