It's not ideal. As a temporary solution for this year it will work if you can get it to hold a stable temperature around 89 degrees and make sure the humidity is staying high enough, 93 is a bit too warm for my comfort. When you go to sleep and cant check it overnight you still want to be sure that the temps aren't getting too extreme.

A cheaper option to a fridge conversion would be a cooler(preferably igloo or something made of plastic) insert some heat tape and a small computer fan, hook the tape up to a thermostat (if you have a separate rack for the babies and only one clutch just buy a nice thermostat for them now an once they hatch move it from the incubator to the rack). The best advice I can give is to do the best you can right now. If the incubator you currently have is the current limit, try to make sure the temps and humidity are spot on and make your best go at it. If you can spare a little money and make an incubator you could use for this year and maybe a few in the future - then do that.

Best of luck to you with your clutch, the surprise of some new eggs is always exciting.