Apply to be a non-preferential creditor if you can prove you had doge there.

Judging by the eth sale I doubt they will directly return coins to creditors. They will probably sell them and return cash instead.

Page 12 of the insolvency/liquidators annual progress report from 26/04/2016 contains a form for letting the liquidator know what you are owed. This is the link to it.

https://beta.companieshouse.gov.uk/company/09009856/filing-history/MzE1MzA3NzYyNWFkaXF6a2N4/document?format=pdf&download=0

According to this filing on 28 January 2021 the insolvency/liquidator's registered office address changed to

Liam Alexander Short,
Elwell Watchorn & Saxton Llp,
8 Warren Park Way,
Enderby,
Leicester,
LE19 4SA.

https://find-and-update.company-information.service.gov.uk/company/09009856/filing-history/MzI4OTU3ODUwM2FkaXF6a2N4/document?format=pdf&download=0

I assume you would send the form there.