Set Initiative of PC to Specific Value (no rolling)

Hello! I am DMing a D&D 5e Monster PC game in which one of my PCs has chosen to be a Mondron.  In our current universe, one of the features of a Mondron (because of their "clockwork" alignment and configuration) is that they do not roll initiative:  their initiative is always 13. I am using the "GroupInititive" api with a simple macro (button command) to automatically roll initiative for all pcs, npcs and enemies.  Currently, I use the automatic api/macro and sit back as all the rolls are populated in the Turn Order Tracker and then manually search for the one PC in order to set their initiative to "13".  At times, this breaks the flow of the game as I have to stop my narration and scroll through many lines just to find one PC.  Is there a macro command that I can use to automatically change that particular PC's initiative to 13 in the TOT after the "automatic" inititives are rolled? I appreciate the help!  Thank you in advance!

Non-api method: just make a macro that adds the selected token to the tracker [[13 &{tracker}]]

Thank you for your response! When I added your suggested line of code to the macro, it changed all initiatives to 13 (I am guessing that this is because the line of code changes all selected tokens on the map to 13).  All the tokens on the map are already selected for the main macro to auto-roll all initiatives at once.  Is there a way to identify one PC (or token) and set it to 13?

I found a solution! If I enter the Modron initiative into the Turn Tracker BEFORE I select everyone and run the macro, the Modron keeps the 13 (it doesn't update the initiative). From there, whenever new combat starts, I simply re-add the Modron first and then select all new enemies, npcs and pcs and run the macro. Thank you for the help!

 [[13 @{selected|token_name}&{tracker}]] for initiative.

Question: YOur method is to select all counters on the map and then roll initiative? Wouldn't that generate a separate initiative for every token? I.e. if you have 20 goblins, wouldn't they all end up with separate initiatives?

You are correct in your statement.  We have very elaborate battles. I give every token an initiative.

Impressive!