The difficulty with "text" and "texted" is surely because of the letters x and t being placed together, which makes the sound usually associated with the past tense. As in "mixed", "fixed", etc.. So it doesn't sound right to add on a further past tense to it ("texted") but is not correct without it either.
Combining "xt" is an awkward sound in Germanic origin languages anyway. In Dutch it is pronounced "s" as in "Texel". "tested" causes no similar problems in being the past tense of "test".
Jessie Glasgwegian is such a different accent from other Scots accents, particularly those on the east coast, it has peculiarities all of its own. Its highly influenced in recent times by Irish Gaelic and was one of the last Gaelic speaking areas in Scotland. I don't think its typical. Some Scots accents also feature a silent "z" when between two consonants, such as in the place name "Dalmunzie". I don't think Scots would struggle any less with "text" and "texted" than the rest of the UK.