Hello Josie100,
If the property is in Receivership, then the Tenant must pay the rent directly to the Receiver. In fact, you are best not to even engage with the tenant, as it may just confuse matters and upset the tenant.
I'm not sure who it is that you are referring to, when you say that you had not declared having a tenant - the Revenue, the Residential Tenancies Board, or the Lender. Regardless, it's up to you to put the matter right and you are not going to get any "assistance" from the Receiver in dealing with the problem, so just tackle it head on. It's better that you contact the relevant party / parties, than have them come to you at a later date.
Any proposal that you want to make needs to go in writing to the Receiver, with copy addressed to Pepper (for the attention of Beltany). I would send the proposal to both parties via registered post, so there is a record of it having been sent.
Expect to be questioned on where funding is to come from, if you are proposing some form of financial settlement. You will probably be asked to swear off a detailed net worth statement, along with statement of income. You may also be asked to have the signing of these documents witnessed by a notary public.