Help with advanced randomization in Qualtrics?

Hi all,
I'm looking for some help on a specific type of randomization I need for my survey. The randomization itself is simple, but the built-in options in Qualtrics aren't equipped to handle it.
I'm setting up a survey for a study on emotion recognition, and the survey uses a subset of the original stimuli that were recognised above chance level in a pilot study. Some emotions were overall better recognised than others, so for example, 16 angry expressions made the final cut whereas only 3 compassion expressions were recognised above chance. For this new survey that I'm building now, I need to tell Qualtrics to 1) randomly select two expressions from each condition (i.e., two of the 16 angry expressions, two of the 3 compassion expressions, etc) and then 2) present this new set of stimuli to participants in a randomized fashion.
The built-in advanced randomization options allow me to get halfway there, but they result in (for example) the two randomly selected anger expressions being presented after each other, rather than mixed in with all the other emotions.
Currently I'm using a convoluted survey flow to first randomly select embedded data (question 1 = show) which I then use to conditionally present the relevant questions in a randomiser (images attached). This works, but given that I have upwards of 400 stimuli to enter into the survey, this is a really inefficient and slow way to work.
I would love some ideas from the community to help me out with this! I don't have a lot of experience with including custom code in the surveys, but perhaps it would be possible to use code (before presenting the questions) to determine the stimuli that will be presented, and then simply present those questions in a randomiser, allowing me to skip the long chunk of setting embedded data (the first image) that I'm using right now.
Any help is appreciated! Thank you,
Lidya
P.s., The stimuli are html links to videos which I'm embedding in the question text. Maybe I could grab them from an excel file and pipe them into the questions to avoid doing it manually?