Internal Salesforce Error: 122688937-111940 (-137733349) (-137733349) after AccountShare record insert.

System.runAs(systemAdminUser) {
            try {
                List<Group> tgroup = [Select Id from Group where RelatedId = :territory.Id and Type = 'Territory'];
                AccountShare ashare = new AccountShare();
                ashare.AccountId = testAccount.Id;
                ashare.UserOrGroupId = tgroup[0].Id;
                insert ashare;
            } catch (Exception e) {
                System.debug(e.getMessage());
            }
            salesForecastList = generateSalesForecasts();
            generateSalesActuals();
            generateSalesGoals();
        }