Personally, I wouldn't let him go. Let him play reserves and fill in for Latu when he's injured. Make him prove his next contract and face the boys every week with his tail between his legs. Will be good for him.
HOWEVER, Manly losing DCE next year means they need a win in the halves and could go all in on Galvin (again Moses has his fingers all over their squad including the coach). If that's the case, I would be open to an end of year swap: GALVIN for OLAKAU'ATU. They need a big name half, we need a top rate 2nd rower. Plus Haumole is very close with the Fainus so could be enticing for him... Would definitely go a long way to sweetening the sour taste left by Galvin.
But I reckon Galvin has got it in his head that he will replace Brown at the EELS and partner the tanker Mitch Moses. They've had coffee together, Isaac Moses has been setting this up, getting in his ear ever since the Brown decision... Not sure there is anyone at Parra that I would want in return, in which case, they can wait to have him in 2027.