I’ve sent a Groupon donation to a lady, but I think that was for something non-essential.  Are there other way to help, besides sending cash in the mail, that are somewhat discrete?  I’d like to help the cause, but I don’t want to get into other trouble for doing so.

you sent them toilet paper, hand sanitizer or paper towels, you were the man of the hour.  Two months later, cash is king.  Buy them a gift card that can be used online.  You keep the card and just give them the card number in order to use it by email or text.  The used up card becomes your receipt for a "charitable contribution" deduction on your taxes.  (Okay, I could be wrong on the last sentence.. Lol)

Not sure what you mean by "discreet" in this context.  (I'm guessing that's a typo.)  
 - Not traceable back to you by the recipient?  
 - Not traceable by spouse?  
 - Not public?  
 - Or ... ?

Western Union money order bought with cash (small fee).  
Visa gift card (not locked to a store!) bought with cash (modest fee).  
CashApp or Venmo drawn on a secret account.  
Amazon gift card paid from a secret account.

You can even purchase these cards in cash and send photos to the provider if you would prefer.

done this several times.   at a CVS (for example)  you can buy a Vanilla Visa card with cash ....   then you can use that card's funds  to purchase and send an Amazon gift card  ..  easier than it sounds and always appreciated.