EnumList being single as single-valued array to AppScript

[maxgonzaga]

I have a bot that triggers when the column Assigned To of type Enum gets changed. This bot runs a AppScript function called assignedToChanged. A bunch of values is passed to this bot, among those is the  column Additional PMs of type EnumList. The problem is that this column is passed as a single-valued array. Example: the column has the values A, B, C; then the script will receive ['A, B, C']. See image below.

What is odd is that I have another bot triggered when the column Additional PMs is updated, and the bot receives the same column as an array of individual values, like this: ['A', 'B', 'C'], which is the behaviour I expected in the situation above.

I would like to know how to make the first bot behave as the second one.