Although the @stack() and @Push() did not work, I resolved the issue with a section script and @IncludeIf. The order of scripts also seems to be important. My Code is:

@section('script')
    <script src="https://checkout.sandbox.dev.clover.com/sdk.js"></script>
    <script src="{{ asset('assets/css/clover-checkout.css') }}"></script>
    <script src="{{ asset('assets/js/clover-checkout.js') }}"></script>
    @includeIf($userBe->is_checkout == 1);
@endsection