The island of St Barthélemy in the Caribbean, Credit: Wikimedia Commons/Remy Gumbs

Quinn Emanuel Urquhart & Sullivan has helped the former managing director of investment powerhouse Bain Capital to win a payout of just over £5 million in a complex two-year London court battle over payments surrounding a luxury Caribbean hotel.

The payout, however, was far below the original sum demanded by the former financier, Mark Nunnelly, who had pressed for more than £28 million in damages related to constructing the hotel in the north Caribbean island of Saint Barthélemy.

Further, the judge, Mr Justice Waksman, at various turns described Nunnelly and his wife's evidence as "at best disingenuous", "implausible" and "unconvincing".

The original dispute centred around claims of financial mismanagement, following a series of investment agreements entered into by a company controlled by Nunnelly and his wife Denise Dupré, Barthélemy Holdings (BH), and an investment management business controlled by Henry Gabay – the Duet Group – and its subsidiary, Duet Trust and Fiduciary Services SA.

Leading for Nunnelly, Quinn Emanuel fielded a team led by partner Matthew Bunting.

The defendant Duet Group was represented by Mishcon de Reya, with partners Masoud Zabeti and Derval Walsh leading the legal team, according to a person involved in the case.

The litigation was one of a number initiated by Duet across the globe, all of which it has lost, according to a spokesperson for Barthélemy Holdings. This is contested by Duet, which said it would continue to "vigorously pursue its claims, which are in excess of €25m".

A spokesperson for Duet Group told Legal Week the court had obliged the other side to indemnify Duet for all the sums awards.

A spokesman for Barthelemy Holdings replied that "this won't affect collection of the award in the slightest".

Duet added: "It is important to note that there is an active French criminal investigation into fraud, breach of trust and concealment" into parties that include Nunnelly, Dupré, their company, Colony Capital and David Schwarz. They added that the judge overseeing the matter is reviewing the case "with a view to taking further steps against the parties under investigation".

Barthelemy's spokesman replied: "Mr Gabay made a complaint in 2017 that was wholly rejected by the French prosecutor. The allegations underlying the complaint were also dismissed by the English judge. Mr Gabay has attempted to renew the complaint, but we are confident that this too will be rejected in due course."

Nunnelly's company, BH, claimed a breach of agreement over misleading budgets by Duet, when the overall cost of the construction amounted to more than double the final cost, for which it claimed Duet was liable.

The ruling saw BH claim back some of the construction costs, as well as legal fees owed to U.S. firm Ropes & Gray for previous advice it had given on investment agreements.

A counterclaim, made by Duet's legal team against BH and Colony, which claimed that the two firms had colluded against it over the sale, was dismissed outright by the judge.

A spokesperson for Barthelemy Holdings commented in a statement: "This is a significant, multimillion-dollar victory for Barthelemy in a long-running dispute, in which Duet has lost at every turn.

"The judgment confirms that Duet mismanaged the hotel and misrepresented its costs, and Justice Waksman recognised the 'absurdity' of Duet's counterclaim."

UPDATE: This article has been updated with additional parts from the judgment and comments from Duet Group.