Ubuntu has been going through some issues driver wise (glitching after EOL of several legacy repos), and sometimes not every program will render out the right pipe. USB shared printers never seem to work well in linux. Try the native OS printer detection once your network sees the printer mac/ip (LPR mode should work). Note too, some printers disappear/reappear on network change overs.
What is the make/model/year where you can't reach the printer web-page on the IP?