glmmTMB截断分布模型的链接尺度预测值反转换方法求助

我正在使用glmmTMB拟合截断计数分布模型，希望在链接尺度上进行预测并对结果进行反转换。此前的相关问题解决了响应尺度的截断分布预测，但由于我的样本量较小、变异性高，响应尺度预测的置信区间下限会低于0，因此我关注链接尺度的反转换方法。如示例所示，简单使用exp()进行反转换显然是错误的，因为结果未考虑截断因素，恳请提供帮助！

library(dplyr)
library(extraDistr)
library(glmmTMB)
library(ggplot2)

set.seed(1)
df <- data.frame(Group = rep(c("a", "b"), each = 20),
                 N = rtpois(40, 1, a = 0))
m <- glmmTMB(N ~ Group, data = df, family = "truncated_poisson")

preds <- predict(m, type = "response", se.fit = TRUE)
df$PredResponse <- preds$fit
df$PredResponseLower <- preds$fit - 1.98*preds$se.fit
df$PredResponseUpper <- preds$fit + 1.98*preds$se.fit

preds <- predict(m, type = "link", se.fit = TRUE)
df$PredLink <- exp(preds$fit)
df$PredLinkLower <- exp(preds$fit - 1.98*preds$se.fit)
df$PredLinkUpper <- exp(preds$fit + 1.98*preds$se.fit)

df %>%
    group_by(Group) %>%
    mutate(Mean = mean(N)) %>%
    ggplot() +
    geom_point(aes(x = Group, y = Mean), size = 5) +
    geom_point(aes(x = Group, y = PredLink, colour = "Link")) +
    geom_point(aes(x = Group, y = PredResponse, colour = "Response")) +
    geom_errorbar(aes(x = Group, ymin = PredLinkLower, ymax = PredLinkUpper, colour = "Link")) +
    geom_errorbar(aes(x = Group, ymin = PredResponseLower, ymax = PredResponseUpper, colour = "Response"))

内容的提问来源于stack exchange，提问作者user2602640