[2020] Prized Possession episode achievements bug

So today I decided to re-run the HoT story for another box of Viper gear and, although I am not the achiever kind of player, I thought why not kill two birds with one stone and get some Mastery points while I'm here (because, really, I can't be arsed to do DS again in my life).

Except it seems impossible to do the achievements right now because the "Echo of Glint" form is bugged. Right after you pick up Glint's egg you transform into the "Echo of Glint" and get shiny wings to fly through the Mordrem vines on your way, but passing through the second vine does not unlock the #1 skill (the short leap) anymore it seems, although the skill slot seems to have changed (the padlock turns into a blank grey skill).

Screenshot

Which means you can't climb the cliff to avoid getting hit and can't collect the blue orbs. Nonetheless I managed to get to Ruka with a few tricky jumps and unlock skill #3 but that does not help for both achievements. I could finish the Prized Possession episode just fine with only #2 and #3 but had to say goodbye to the mastery point. I replayed the episode ten times without success until I could not endure the dialogues anymore and gave up.

Now I'm not too sure if I'm doing something wrong or if it actually is a bug. I looked on both Reddit and the forum but can't seem to find anything related. Did I miss something on the way to unlock the skill?

[Edit] Known issue tracker confirmed it is a bug so I guess I'll just pass...