This thread is resolved. Here is a description of the problem and solution.
Problem: I have customised a couple of woocommerce checkout LABELS, but they do not appear in the string translations. I need to translate those labels, but I cannot find them in the string translation panel. Solution: All you have to do is wrap the string in gettext as explained here https://wpml.org/faq/language-setup/
This is the technical support forum for WPML - the multilingual WordPress plugin.
Everyone can read, but only WPML clients can post here. WPML team is replying on the forum 6 days per week, 22 hours per day.