It doesn’t hurt to ask, all they can say is “no”. However I wouldn’t expect much, if any, additional funding.
Also, the colleges are likely to ask you to complete the FAFSA before they give you any financial aid. Your not having done this earlier is a huge flashing sign to them that you’re fully aware that you are capable of paying 100%. Be prepared to document any changes in your personal finances that indicate otherwise.
While enrollments may be down at some colleges, they may not necessarily be looking to replace those students. If they are planning to return to campus in the fall, they may be looking to thin out for social distancing, more single dorm rooms, etc.