Assalamu alaikum, putting links to gambling websites is totally haram! You are encouraging people to gamble this way and you should decline these offers since it goes against Islam. Doing this can give you many sins, people could log into your website and click these sponsors and start gambling. You will get sins since they acted upon what you guided them towards and each time someone does it, you get a part of the guilt.
Abu Huraira reported: The Messenger of Allah, peace and blessings be upon him, said, “Whoever calls to guidance will have a reward similar to those who follow him, without detracting from their rewards at all. Whoever calls to misguidance will have sin upon him similar to those who follow him, without detracting from their sins at all.”
Source: Ṣaḥīḥ Muslim 2674
So please, avoid doing this and focus on what's right.