I am assuming when you say Pioneer 503, you are referencing this specific model...
intl.pioneer-audiovisual.com
What is it you're hoping to do here?
The Lenovo Smart Display (which I have never heard of)...
Check out the Lenovo smart display android tablets with Google Assistant. Play music, watch videos, get answers, make video calls, & control your smart home.
www.lenovo.com
Appears to be a stand alone device. What is your expectation, hope, desire, or intent with these two devices?
Odds are good that both devices are Chromecast receiving devices, not transmitters. So, you can't likely go from the Lenovo to the Pioneer or vice-versa. While Lenovo advertises it as being able to just 'work' to send stuff to your TV, that's NOT really how Chromecast works and it shouldn't be expected to work well.
Wireless sucks. It's a myth. It's BS. If the product isn't working between the Pioneer and the Lenovo, then it's quite likely some sort of firmware mismatch or other incompatibility, and emphasizes how unreliable wireless, especially Chromecast, can be.