Update: After spending multiple days on it I found a solution. By adding min-w-max it suddenly worked and the boxes kept the width and the scroll was like it was expected.

 <div class="w-4/5 ml-[25%]">
        <div class="overflow-sroll">
            <table class="table-fixed overflow-sroll min-w-max">
                <thead>

The margin on the right however does not work in any way (guessing the min-w-max class does it) but I do not mind anymore.