I'd take it back to the same shop and show them the receipt and tell them of the existing problems. If they'll make it right & not charge you, then fine. If they give excuses or won't make it right with no charge, then I'd take it to another shop. Or, if the shop is a bit of a drive, I'd call them first and explain the situation.

Personally I quit taking my boat to dealers/shops and take it to a fella over in Georgetown that does the work at his home. I actually had some "triggers" go bad on my motor & had him fix it.