Take a bottle of "Simple Green" and weigh it on a postage scale. Then spray the areas of oil mist, trying to cover the same surface area and density of the misted area. Don't forget to do the towel, also. Weigh the bottle. Take ~difference (oil is lighter than water, I know) and you've got a great approximation of how much oil was lost...........AND you've cleaned up the mess
. I think it will be less than you imagine.
Reclaim the R134a, add the amount of oil needed, vacuum and charge. At least it worked on paper
.