Would it be out of the question to instead just create the fields inside of Quickbase itself on the form and have them fill those out? It could be done in a similar way and the fields/answers would still be associated with the record it just would not be attached as a file. This record link could be shared instead of the Excel file if it requires sharing.
If you wanted you could then move this to excel weekly or monthly, whatever you wanted, by just exporting it.
Another option would be to simply have a link point them to office 365 Excel or whatever they use. Then they could click that and do their task, save it, and add it to the record.
You may also be able to embed it as a web page in the home page but I think that is unlikely to run well in the end, you could try it though and see. It may not work at all I didn't test it.
Not sure I fully understand your use case here. More information may be needed to communicate exactly what you want.
I agree that having the fields in Quickbase is ideal. Once the data is entered you could eliminate the manual step of emailing the spreadsheet by having an email notification trigger when the data is entered and it could include the data that was entered. If the spreadsheet format is important for getting people to adopt Quickbase, the spreadsheet can be published as a webpage and the HTML code can be entered into a code page. Then you can enter Quickbase field syntax and turn your Excel HTML code page into a custom form. The form can then be embedded on the home page. It is a bit tedious and requires some low level coding ability, but it can be done.
Here is an example of an Excel sheet published as a webpage, the code added to a code page, fields mapped to Quickbase, and embedded on a home page:
Here is an example of the syntax for posting the data entered in the code page form to Quickbase as a new record: