Yup, you are right. Phones will keep collecting data point. It will upload as soon as it gets connected. But location can still be provided near realtime via Bluetooth on newer Android and iOS devices. This will happen even if device is offline.

Yup, some websites outright deny non chromium browser

Change you browsers user-agent(set to chrome on windows), clear cookies & disconnect router for 1 min. Then try again. Let me know if it works 😀

Probably he might fire you after getting trained staffed. This is very old strategy. Hold onto a employee till a cheaper replacement. Enjoy while it last start searching for better company