https://www.youtube.com/watch?v=key9ovLTJZE&list=PLMSHPuWvcbGdpbxg06R-F3AbRp1-CmyWr This is your video for variable timing, right here! Also if you want to check if the timing is correct for a variable BPM map, well, just check one timing point first. You do that by putting the song at 25% or whatever slower playback speed and check if the big, booming downbeats of the music line up perfectly with every single mentronome ticks for like at least 20-30 seconds. If it's unaligned with even one of those ticks at any moment in those 20-30 seconds, then the timing is off and you need to keep on timing the map.
So for your beatmap, yeah, I can tell the timing is farrr from correct for the end, unfortunately, because the downbeats are not really lining up with any tick in the timeline, so ask someone in a discord server if you need even more help with timing a map than the video that I linked can give you, which I think you will definitely need anyways, just saying.