Multiple entry/exit Malaysia to do Registration of marriage and LTVSP

Hi,

My boyfriend and i would like to get married in Malaysia and we are now currently waiting for his marital status declaration document before proceeding.

As his tourist visa is expiring in a bit more than one month time, from the infos i've gotten is that below 80 days he just needs to go out for 3 days, but if above 80 days its 7 days. We are planning for him to go out on the 77 or 78th day to Thailand for 3-4days before coming back into Malaysia. By then we would already have registered made an application for registration of marriage.

My concern now is will be prevented from entry during his second entry into Malaysia? And if so, will a receipt/document to show that we're already registered for marriage be sufficient proof for him to enter the second time?

As we want to apply for LTVSP after his second entry, however i've read about the minimum to wait for 6 mths before such application, is there a way to shorten this wait and apply it after a month of marriage?
Will a second visa run / third entry to Malaysia for the reason to complete the LTVSP would allow him in again?

I've heard of a visa called visa with reference, can someone advise me how long is this visa for, and when/how do i apply for this and it's requirement? Or if this visa gets rejected, will it affect his tourist entry the next time?

Please advise how should i proceed with the planning and arrangement of dates.

Thank you very much