My Father Aged 67 With Diabetes And Blood Report Showed Bilirubin At 6.7mg/dl, Elevated Levels Of SGOT, SGPT

Question: Good Morning Sir,
My father aged 67 with Diabetes and Hypertension has suffered from Obstructive Jaundice from 2 weeks.
The blood report showed Bilirubin at 6.7mg/dl, elevated levels of SGOT, SGPT.
But his Ca19-9 came at 194 u/l ( Normal <37).
Abdomen USG was normal.
Two days later, his Jaundice symptoms started subsiding.
Upon consultation with Gasteroenterlogist, ordered again blood tests and MRI With MRCP.
His bilirubin came down to 1.8 (normal <1.2),
Ca19-9 came at 73u/l (normal <27).
His MRI with MRCP showed Galbladder stones.
MRI +MRCP report is attached herewith.
My question is,
1. Is it still required to under go removal of Galbladder even in the absence of any pain
2. I request you to kindly check MRI scan reports in view of Ca19-9 levels. More over Ca19-9 levels came down from 194 to 73u/l with in less than 1 week without any treatment.
Thanking You, Sir
Yours Sincerely.

Sir, Reports are attached herewith.
During Jaundice time,
His Bilirubin was 4.4, 6.6 and after 4 days it came down to 1.8.
Ca19-9 was 194 during jaundice. He is a moderate smoker. He quit smoking for 1 week during jaundice
(presently also) and his ca19-9 came down to 73 in 4 days.
His MRI With MRCP is attached herewith.
Is his elevated Ca19-9 is only due to smoking and gallstones?
Regarding Gallstones, he is completely out from his Jaundice symptoms. Is it OK if we wait and see before taking any decision on Gallbladder removal?
Thanking You Sir.

Sir, just to add,
He is on Diabetic medications for the last 32 years, on Hypetension medicines for last 8-10 years.