That sounds frustrating — I ran into something similar with my Galaxy device. One thing to check is whether your work Wi-Fi network blocks certain ports or prioritizes traffic differently, which can prevent Wi-Fi calling from kicking in. Since your work iPhone handles it fine, it could be that iOS and Android use slightly different protocols or port ranges for Wi-Fi calling.
You might also try toggling airplane mode with Wi-Fi on while at work — that sometimes forces the device to skip searching for a cellular signal and jump straight to Wi-Fi calling. I rely on this a lot since I work in medical billing remotely, and a stable connection is critical. I run my daily operations through https://ebillingworks.com/, and solid Wi-Fi calling has been a lifesaver when cell service drops.
