Hello @Rolo7
WiFi clients (like your TV) decide which access point to connect to. Google WiFi provide some "extra" information some clients can use to make better decisions, but many clients don't support the standards used for that (802.11k and 802.11v). Fixed devices (like your TV) would be unlikely to do so, which leaves them often connecting to the first access point that starts up (typically the primary/router unit). They can often end up "sticking" to that access point as long as it continues to work – even when the TV is powered off (it's often just mostly off, and if The Princess Bride has taught me anything, there's a big difference between "off" and "mostly off").
You might have some success by unplugging the TV from power for 30 seconds or so in hopes it connects to a better access point when it starts up. You may have to repeat this any time you restart your Google WiFi network.
If that doesn't work, you might see if your TV has an Ethernet port on the back. If it does, since you have Google WiFi, you could just connect the TV directly to that nearby Google WiFi unit using an inexpensive Ethernet cable and skip using WiFi for that link entirely. That would be the most reliable and efficient connection option.
