Watson's housewarming party will come as London, the epicentre of the UK's Covid-19 outbreak, steadily shuts down in a bid to contain the virus. Many underground stations have closed, pubs have been ordered shut, and even Prime Minister Boris Johnson has been diagnosed with the disease.
Watson gained fame in New Zealand in the 1990s and 2000s as a playboy businessman, dating lingerie models, owning the New Zealand Warriors and being part-owner of ultimately failed finance company Hanover.
In recent years he has become better-known for being on the losing end of titanic legal struggles with both the tax department and former business partners. The aftershocks have seen liquidators appointed to most of Watson's New Zealand-domiciled companies.
Last year his Cullen Group lost a long-running dispute with the Inland Revenue Department over allegations that a complex structure of loans transactions in 2002 involving Cayman Island companies amounted to avoidance.
The ruling saw Cullen made liable for $112m in back-taxes and interest costs. In April Cullen filed an appeal.
A spokesperson for Inland Revenue cited tax secrecy provisions in their governing legislation and said: "We cannot say anything about the tax affairs of individual New Zealanders".
Last year Watson lost his appeal against a UK court ruling that he must repay Sir Owen Glenn $87m plus interest after a joint venture between the pair soured. Watson had earlier told the courts he was unable to pay the judgment as he did not have the assets to do so.
A representative for Glenn told the Herald that the amount owed remained outstanding. "Your assumption that no payment has been volunteered by [Watson] is correct although, as you will appreciate, through his legal teams in UK and also in New Zealand and USA, Sir Owen remains committed to enforcement and ensuring that his former business partner simply pays what is owed."
Watson, who left New Zealand in 2002 to relocate to London, has in recent years severed his remaining business ties with this country. One of his last moves was to offload the Warriors - a debt-laden club he'd bought for $1 in 2000 - for around $18m.
Last week the Warriors' new owners pulled the pin on their involvement in the NRL season - inevitably taking a huge financial bath - over Covid-19 restrictions and concerns.