Hillary Clinton's Big Hollywood Donors Left Hanging

1:01 PM PST -- TMZ has confirmed Bill Clinton will appear at both events on Hillary's behalf.

Hillary Clinton's campaign charged up to a hundred thousand dollars for fundraisers in L.A. she may well not attend.

It's a big deal ... the rich and famous were expecting to rub elbows with Hillary at Seth MacFarlane's home. There was also an "intimate dinner with Hillary" at billionaire Barry Diller's estate.

For lunch at the "Family Guy" creator's pad -- donations start at $5k ... $10k gets you "co-host" status with preferred seating ... and for a whopping $33,400 you get a photo with HRC.

Dinner at the home of Barry and Diane von Furstenberg's a tad steeper -- $100k per couple.

The campaign said Monday Hillary will be back on the campaign trail by the middle or end of the week ... and it's likely she'll miss the 2 fundraisers due to pneumonia.

We're told the donors have already shelled out the money and received Secret Service clearance.