Checkboxes not transferring properly between Google Sheets and Excel

Hey folks!

A while ago I created a simple little spreadsheet in Sheets for the purposes of making my job of creating a work schedule easier. The idea is simple: each employee has a row, with three columns for each work day. For each day there is an "Off?" section that has a checkbox, and columns for "In" and "Out".

Checking the checkbox sets off a Conditional Formatting rule for the cells in the next two columns over that greys out those two cells. It looks like this. https://imgur.com/a/tlxEorz

Admittedly, this was very cumbersome to do and that makes me reluctant to scrap it all and work from a different starting point.

Only problem is that when I export it as an excel file and pull it up, all of my checkboxes are gone and replaced with TRUE/FALSE text. I see that checkboxes function differently in Excel than they do in Sheets, but I don't exactly understand it.

The conditional formatting does still work if I type in TRUE/FALSE, but I want to be able to interact with a checkbox like I can already do in Sheets but my Insert Checkbox button is greyed out no matter what I do. The workbook is unprotected, so I'm not sure what's going on.

Does anyone have any ideas on how to get this functioning in Excel? It won't necessarily need to be transferable back to sheets, I really just need it functioning in Excel because that's what my new job uses.

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