4 week old Zucchini with crispy

[LCgarden]

These plants have gone through a significant amount of stress lately. Theyve been in and out of a dim garage due to freak snow and cold weather. I may have underwatered them. I thought I hardened them off and a few of the cucumbers in the same tray got scorched but 2 of the zucchini plants one leaf each had these on them. The spots are crispy and dry on the underside. Should I throw the plants I cut these out from away? They are otherwise totally healthy looking they have maybe 3-4 other leaves. Please help. If it’s bacteria I don’t want it to spread!