If the bug is as observed, that the random_list command always returns/executes the first element in the list, then that command will have to be fixed by devs. For a "field expedient" quick fix by users though, one could:
1) find all occurrences of random_list in the events, and for each occurrence:
2) aggregate the effects in the list into one set of averaged effects (e.g. if there is a 90% of +10 & a 10% chance of +20, then make it a 100% chance of (.9*10 + .1*20) = +11.
In this way, the events would have the intended gameplay effects, the same as they would have with a properly functioning random_list command (over many iterations) although without the randomness.