You can, but you are referencing the subquestions wrong.
You need to tell Limesurvey which question you are referring to and which subquestion you are referring to. AS So what is the question code of this array question? Because Q12-Q16 seem to be the subquestion codes.
So to reference the subquestions you need to go like this QUESTIONCODE_SUBQUESTIONCODE. If you would use numbers for the answer codes you could shorten your equation quite a bit by use >, < and = to define everything in one.
Lets assume you want to reference the subquestion Q12, lets assume the question code of the whole question is QC and the answer options are 1-5 and you only want 1-3 go further.
Then you could write something like this:
If you put this into the long free text question as relevance equation, the question would open if the respondent answere 1, 2 or 3 in subquestion Q12 of question QC.
If you really want to stick to your current answer codes it will be more or less the same, you just will have to have a longer relevance equation.