As you suspected, your video uses the HEVC H.265 video codec, which is not well supported by Premiere Elements.
The video is also an unsupported resolution (2704x2028).
You can try converting the video to a 1920x1080 30 fps MP4 using the free download HandBrake -- but because your video has ans aspect ratio 4:3 rather than 16:9, it's going to "float" with black bars on the right and left to fill out the video frame.
In my opinion, you're going to find this video editing software very frustrating to use with this video. I'd consider either test driving Premiere Pro CC (subscription) or CyberLink PowerDirector Ultimate (about the same price as Premiere Elements).